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TI-2026-74922 Aliases CVE-2026-111138

Out-of-bounds read in NetSurf libnsbmp RLE8 and RLE4 decoders

Priority MEDIUM 63CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

Summary

NetSurf libnsbmp through 0.1.7 has an out-of-bounds read in its RLE8 and RLE4 BMP decoders, where bound checks for absolute runs omit the word alignment pad byte (CWE-125). If a user decodes a crafted RLE8 or RLE4 BMP that ends on an odd-length absolute run, a one-byte heap over-read crashes the application. A public exploit is linked in the references.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

NetSurf libnsbmp through 0.1.7 contains an out-of-bounds read vulnerability in bmp_decode_rle8() and bmp_decode_rle4() because absolute-run bound checks omit the word-alignment pad byte. Attackers can supply a crafted RLE8 or RLE4 BMP ending on an odd-length absolute run to cause a one-byte heap over-read, crashing applications decoding untrusted images.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00128 2nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
NetSurflibnsbmpup to 0.1.7—No fix listedCNA
  • libnsbmp VendorNetSurf Affected up to 0.1.7 Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for libnsbmp.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-16 Threatist record created from CVE-2026-111138
  2. 2026-10-16 Affected versions changed · Red Hat
  3. 2026-10-16 CVSS score added · Red Hat

References

Exploit 1

Other 4

  • TI-2026-74923 Out-of-bounds read in NetSurf libnsbmp via crafted ICO files CVSS 4.0MEDIUM 6.8

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences