ZDF
Sign inSign up

Vulnerabilities

Vulnerability · CVE-2026-61627

libass: Out-of-bounds read and write in wrap_lines_measure

Published Oct 30, 2026 · catalog updated Oct 31, 2026 · libass: Out-of-bounds read and

Last checked Nov 6, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-2026-61627. EPSS is 0.15%. Act only if a listed version of libass: Out-of-bounds read and is installed.

Gaps on this record

  • The stored product name is a package slug. The name on this page is taken from the title (libass: Out-of-bounds read and).
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.

Same product and reporting

Severity
High7.3
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.15%
Remediation
Advisory link
Affected products
Debian:12 libass · Debian:13 libass · Debian:14 libass · vendor libass libass

libass is a portable subtitle renderer for the /SSA (Advanced Substation Alpha/Substation Alpha) subtitle format. Prior to 0.17.5, libass can overread and overwrite the glyph array in while rendering malicious content. In , a final line ending with a literal backslash-n sequence and otherwise consisting only of such sequences or spaces can remain after early trimming and make the line-measurement loops overshoot by one glyph. When the total text size exactly matches the allocated glyph-array capacity, the first loop reads an uninitialized 32-bit fixed-point value, although that value is not subsequently used. The second loop writes and beyond the array, zeroing the first and adding an attacker-controllable offset to the second. No actual exploitation beyond possible denial of service is known; broader exploitation is theoretical and constrained by the addresses, limited writes, and ASLR. This issue is fixed in version 0.17.5.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • Debian:12 libass0 → 1:0.17.1-1+deb12u1
  • Debian:13 libass0 → 1:0.17.3-1+deb13u1
  • Debian:14 libass0 → 1:0.17.5-1
  • vendor libass libassversion unspecified

How to fix CVE-2026-61627

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-61627. EPSS is 0.15%. Act only if a listed version of libass: Out-of-bounds read and is installed.

Which versions are affected?

Compare what you have installed with 0 → 1:0.17.1-1+deb12u1, 0 → 1:0.17.3-1+deb13u1, 0 → 1:0.17.5-1. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-125: Out-of-bounds Read; CWE-787: Out-of-bounds Write. EPSS 0.15%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Technology hubs

Debian security

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 30, 2026 · Trivy Vulnerability DB

    Detected

  2. Oct 30, 2026 · Trivy Vulnerability DB

    Fix available

    libass fixed in 1:0.17.1-1+deb12u1; libass fixed in 1:0.17.3-1+deb13u1; libass fixed in 1:0.17.5-1

  3. Oct 30, 2026 · Trivy Vulnerability DB

    Fix available

    libass fixed in 1:0.17.1-1+deb12u1

  4. Oct 30, 2026 · Trivy Vulnerability DB

    Fix available

    libass fixed in 1:0.17.3-1+deb13u1

  5. Oct 30, 2026 · Trivy Vulnerability DB

    Fix available

    libass fixed in 1:0.17.5-1

  6. Oct 30, 2026 · Trivy Vulnerability DB

    Updated

    The description or metadata changed.

  7. Oct 31, 2026 · Trivy Vulnerability DB

    Updated

    libass is a portable subtitle renderer for the /SSA (Advanced Substation Alpha/Substation Alpha) subtitle format. Prior to 0.17.5, libass can overread and overwrite the glyph array in while rendering malicious content. In , a final line ending with a literal backslash-n sequence and otherwise consisting only of such sequences or spaces can remain after early trimming and make the line-measurement

Sources

  • CVE.orgVulnerability recordCVE-2026-61627

    libass is a portable subtitle renderer for the /SSA (Advanced Substation Alpha/Substation Alpha) subtitle format. Prior to 0.17.5, libass can overread and overwrite the glyph array in while rendering malicious content. In , a final line ending with a literal backslash-n sequence

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-61627

    30-day exploitation probability 0.15%

    first.org
  • Trivy Vulnerability DBPackage advisoryDEBIAN-CVE-2026-61627

    libass is a portable subtitle renderer for the /SSA (Advanced Substation Alpha/Substation Alpha) subtitle format. Prior to 0.17.5, libass can overread and overwrite the glyph array in while rendering malicious content. In , a final line ending with a literal backslash-n sequence

    osv.dev

References

Freshness

Last verified in this catalog Nov 6, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • FIRST EPSSOct 31, 2026
  • Trivy Vulnerability DBOct 31, 2026
  • CVE.orgOct 30, 2026