synced 2 MIN AGO
01 Record

CVE-2026-42533

NGINX Map directive and Regex matching vulnerability

CriticalPUBLISHEDCNA: f5
CNA base score9.2 CVSS v4.0CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
View raw JSON

02 Description

NGINX Map directive and Regex matching vulnerability

03 Exploitation and scoring

Exploitation
Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.
SSVC decision
  • ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
  • AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
  • Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.
EPSS probability
0.89% probability of exploitation activity in the next 30 days.
EPSS percentile
Equal to or higher than the score of 59.3% of scored records. A rank, not a probability.
NVD base score
9.2 (CVSS v4.0), scored by the NVD independently of the CNA.
NVD CVSS vector
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD analysis status
Analyzed. NVD last modified this record on 2026-08-10.
Red Hat severity
Important. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published
2026-07-15 14:33Z3 MO AGO
Last updated
2026-07-29 03:55Z3 MO AGO
Reserved
2026-05-05
Assigning CNA
f5
Record state
PUBLISHED
Severity
Critical (CVSS 9.2)
CNA CVSS vector
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weaknesses
  • CWE-122Heap-based Buffer OverflowVariant
  • CWE-131Incorrect Calculation of Buffer SizeBase
Data version
5.2
Document digest
55e3a2ad09d11ba88e6fc1343295443194649796e1c015becce30b7e72827014

05 Affected products

VendorProductVersionsPlatforms
F5NGINX Plus37.0.0.1 to < 37.0.3.1, R36 to < R36 P7, R33 to < *—
F5NGINX Open Source1.31.2 to < 1.31.3, 0.9.6 to < 1.30.4—

06 References

07 Fixed in

AlmaLinux 8

  • nginx
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-all-modules
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-filesystem
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-devel
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-http-image-filter
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-http-perl
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-http-xslt-filter
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-mail
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-stream
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

AlmaLinux 9

  • nginx
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-all-modules
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-core
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-filesystem
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-devel
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-http-image-filter
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-http-perl
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-http-xslt-filter
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-mail
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-stream
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

AlmaLinux 10

  • nginx
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-all-modules
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-core
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-filesystem
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-devel
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-http-image-filter
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-http-perl
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-http-xslt-filter
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-mail
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-stream
    Fixed in 2:1.26.3-6.el10_2.7

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

CloudLinux 8

  • nginx
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-all-modules
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-filesystem
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-devel
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-http-image-filter
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-http-perl
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-http-xslt-filter
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-mail
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1
  • nginx-mod-stream
    Fixed in 1:1.24.0-3.module_el8.10.0+4275+5756017d.5.alma.1

Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

CloudLinux 9

  • nginx
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-all-modules
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-core
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-filesystem
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-devel
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-http-image-filter
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-http-perl
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-http-xslt-filter
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-mail
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4
  • nginx-mod-stream
    Fixed

    A version is affected if any line below covers it.

    • Affected before 1:1.24.0-7.module_el9.8.0+307+7a7a3a71.5.alma.1
    • Affected before 2:1.20.1-28.el9_8.6.alma.1
    • Affected before 2:1.26.3-9.module_el9.8.0+309+b8a3c30d.4

Derived from AlmaLinux 9. Partial coverage: only packages taken from AlmaLinux 9 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

CloudLinux 10

  • nginx
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-all-modules
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-core
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-filesystem
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-devel
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-http-image-filter
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-http-perl
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-http-xslt-filter
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-mail
    Fixed in 2:1.26.3-6.el10_2.7
  • nginx-mod-stream
    Fixed in 2:1.26.3-6.el10_2.7

Derived from AlmaLinux 10. Partial coverage: only packages taken from AlmaLinux 10 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

Debian 12

  • nginx
    Fixed in 1.22.1-9+deb12u10

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 13

  • nginx
    Fixed in 1.26.3-3+deb13u8

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 14

  • nginx
    Fixed in 1.30.4-3

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 22.04 LTS

  • nginx
    Fixed in 1.18.0-6ubuntu14.21

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 24.04 LTS

  • nginx
    Fixed in 1.24.0-2ubuntu7.18

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 26.04 LTS

  • nginx
    Fixed in 1.28.3-2ubuntu1.11

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 14.04 LTS

  • nginx
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 16.04 LTS

  • nginx
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 18.04 LTS

  • nginx
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 20.04 LTS

  • nginx
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.