Invoking infinite loop on large channel writes in golang.org/x/crypto/ssh (golang.org/x/crypto golang.org/x/crypto/ssh)

CVE-2026-39834
CRITICAL 9.1

At a glance

Source
NVD
EPSS
EPSS 0.60 % · percentile 49 ()
State
PUBLISHED
Published
Updated
Assigner
Go
NVD status
Analyzed

Description

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

Weaknesses (CWE)

  • CWE-190 — Integer Overflow or Wraparound

References

Scores

VersionScoreVectorScored by
CVSS 3.1CRITICAL 9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:HCISA-ADP
CVSS 3.1CRITICAL 9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:HNVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)

Advisories

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
golang.org/x/crypto · golang.org/x/crypto/sshaffected 0 < 0.52.0

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD