CVE-2026-27889

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.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited 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

0.58% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 45.5% of scored records. A rank, not a probability.

NVD base score

7.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

NVD analysis status

Modified. NVD last modified this record on 2026-08-24.

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.

Published

2026-03-25 19:36Z5 MO AGO

Last updated

2026-08-24 12:07Z11 DAYS AGO

Reserved

2026-02-24

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

High (CVSS 7.5)

CNA CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses

• CWE-190Integer Overflow or WraparoundBase
• CWE-1286Improper Validation of Syntactic Correctness of InputBase

Data version

5.2

Document digest

78c020ee2b0e9f64a8d4ab31e4cdf7e32bf343c404fa51b2ae151c696885cdeb

• github.comhttps://github.com/nats-io/nats-server/security/advisories/GHSA-pq2q-rcw4-3hr6x_refsource_CONFIRM
• advisories.nats.iohttps://advisories.nats.io/CVE/secnote-2026-03.txtx_refsource_MISC
• access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-27889vdb-entryx_refsource_REDHAT
• bugzilla.redhat.comRHBZ#2451447https://bugzilla.redhat.com/show_bug.cgi?id=2451447issue-trackingx_refsource_REDHAT
• security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27889.jsonx_sadp-csaf-vex
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:21769vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:22347vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:23345vendor-advisoryx_refsource_REDHAT