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Fencer Vulns
medium 5.3

CVE-2026-42500 json

Panic when reading out of bound palette index in golang.org/x/image/bmp

published 2026-05-29 5 mo ago modified 2026-09-22 48 d ago also GO-2026-5031 , EUVD-2026-33419

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 32%
public exploits
0
none known

Summary

Decoding a paletted BMP file with an out-of-range palette index results in a panic when accessing pixels in the invalid image.

Patch / fix

  • go golang.org/x/image 0.41.0
  • golang.org/x/image golang.org/x/image/bmp 0.41.0
  • golang-golang-x-image Debian 14 0.42.0-1

debian advisories DEBIAN-CVE-2026-42500

  • golang1.27 hummingbird 1 1.27.1-0.1.hum1
  • golang1.27-bin hummingbird 1 1.27.1-0.1.hum1
  • golang1.27-src hummingbird 1 1.27.1-0.1.hum1
  • golang1.27-misc hummingbird 1 1.27.1-0.1.hum1
  • golang1.27-tests hummingbird 1 1.27.1-0.1.hum1
  • golang1.26 hummingbird 1 1.26.8-0.1.hum1
  • golang1.26-bin hummingbird 1 1.26.8-0.1.hum1
  • golang1.26-src hummingbird 1 1.26.8-0.1.hum1

red hat advisories RHSA-2026:66561RHSA-2026:62391

  • govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
  • rclone openSUSE Leap 16.0 1.74.4-bp160.1.1
  • rclone openSUSE Tumbleweed 1.74.2-1.1

opensuse advisories openSUSE-SU-2026:21483-1openSUSE-SU-2026:21436-1openSUSE-SU-2026:10856-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-42500 updated cvss 6.5

golang.org/x/image/bmp: golang: golang.org/x/image/bmp: Denial of Service via out-of-range palette index in BMP decoding

  • Red Hat Hardened Images golang1.25
    affected: workaround, no fix planned “No mitigation is available for this vulnerability.”
  • Red Hat Hardened Images golang1.26 1.26.8-0.1.hum1, golang1.27 1.27.1-0.1.hum1, golang1.26-bin 1.26.8-0.1.hum1, golang1.26-src 1.26.8-0.1.hum1, golang1.27-bin 1.27.1-0.1.hum1, golang1.27-src 1.27.1-0.1.hum1, +4 more
    fixed: vendor fix “No mitigation is available for this vulnerability.” RHSA-2026:62391

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
5 mo ago

Exploit prediction

0.38% chance of exploitation in the next 30 days, higher than 32% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected packages

ecosystem package affected fixed in
go golang.org/x/image
<0.41.0
0.41.0

Affected products

  • golang.org/x/image golang.org/x/image/bmp

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.