01 Record

CVE-2026-27459

pyOpenSSL DTLS cookie callback buffer overflow

HighPUBLISHEDCNA: GitHub_M

CNA base score7.2 CVSS v4.0CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U

View raw JSON

02 Description

pyOpenSSL DTLS cookie callback buffer overflow

03 Exploitation and scoring

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
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

0.70% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 50.7% of scored records. A rank, not a probability.

NVD base score

7.2 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/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

Modified. NVD last modified this record on 2026-08-31.

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

2026-03-17 23:34Z5 MO AGO

Last updated

2026-09-04 12:04Z7 HR AGO

Reserved

2026-02-19

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

High (CVSS 7.2)

CNA CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U

Weaknesses

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')Base

Data version

5.2

Document digest

ccb11dab539bc61ed27ff8ee25d7c358e165fc11a50d5ab91e3191b155b82b3b

05 Affected products

VendorProductVersionsPlatforms

pycapyopenssl>= 22.0.0, < 26.0.0—

06 References

github.comhttps://github.com/pyca/pyopenssl/security/advisories/GHSA-5pwr-322w-8jr4x_refsource_CONFIRM
github.comhttps://github.com/pyca/pyopenssl/commit/57f09bb4bb051d3bc2a1abd36e9525313d5cd408x_refsource_MISC
github.comhttps://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rstx_refsource_MISC
access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-27459vdb-entryx_refsource_REDHAT
bugzilla.redhat.comRHBZ#2448503https://bugzilla.redhat.com/show_bug.cgi?id=2448503issue-trackingx_refsource_REDHAT
security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27459.jsonx_sadp-csaf-vex
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:13512vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:10754vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:14874vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:13508vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:14873vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:14835vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:13553vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:13545vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:59153vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:48758vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7224vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:11856vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:21017vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:24853vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:19375vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:22465vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:48085vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:11916vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:11996vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8437vendor-advisoryx_refsource_REDHAT

01 Record index

CVE-2026-27459

02 Description

03 Exploitation and scoring

04 Metadata

05 Affected products

06 References

02 Records

CVE-2026-27459

02 Description

03 Exploitation and scoring

04 Metadata

05 Affected products

06 References