CVE catalog
CVE-2026-33636
LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. In versions 1.6.36 through 1.6.55, an out-of-bounds read and
- Severity
- High · CVSS 8.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.75% · Oct 25, 2026
LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. In versions 1.6.36 through 1.6.55, an out-of-bounds read and write exists in libpng's ARM/AArch64 Neon-optimized palette expansion path. When expanding 8-bit paletted rows to RGB or RGBA, the Neon loop processes a final partial chunk without verifying that enough input pixels remain. Because the implementation works backward from the end of the row, the final iteration dereferences pointers before the start of the row buffer (OOB read) and writes expanded pixel data to the same underflowed positions (OOB write). This is reachable via normal decoding of attacker-controlled PNG input if Neon is enabled. Version 1.6.56 fixes the issue.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | libpng1.6 | sid | 1.6.59-1 | fixed |
| Debian | libpng1.6 | forky | 1.6.59-1 | fixed |
| Debian | libpng1.6 | trixie | 1.6.48-1+deb13u5 | fixed |
| Debian | libpng1.6 | trixie-security | 1.6.48-1+deb13u6 | fixed |
| Debian | libpng1.6 | bookworm | 1.6.39-2+deb12u5 | fixed |
| Debian | libpng1.6 | bookworm-security | 1.6.39-2+deb12u6 | fixed |
| Cpe | libpng1.6 | Not reported | 1.6.43-5ubuntu0.6 | fixed |
| Cpe | libpng-dev | Not reported | 1.6.43-5ubuntu0.6 | fixed |
| Cpe | libpng-tools | Not reported | 1.6.43-5ubuntu0.6 | fixed |
| Cpe | libpng16-16t64 | Not reported | 1.6.43-5ubuntu0.6 | fixed |
| Cpe | libpng | Not reported | 1.6.56 | fixed |
| Android | platform/external/libpng | Not reported | 14 | vulnerable |
| Android | platform/external/libpng | Not reported | 14:2026-09-01 | fixed |
| Alpine | libpng | 3.20 | 1.6.56-r0 | fixed |
| Alpine | libpng | 3.21 | 1.6.56-r0 | fixed |
| Alpine | libpng | 3.22 | 1.6.56-r0 | fixed |
| Alpine | libpng | 3.23 | 1.6.56-r0 | fixed |
| Alpine | libpng | 3.24 | 1.6.56-r0 | fixed |
| Ubuntu | libpng1.6 | pro | 1.6.37-1 | vulnerable |
| Ubuntu | libpng1.6 | pro | 1.6.37-2 | vulnerable |
| Ubuntu | libpng1.6 | pro | 1.6.37-2ubuntu0.1~esm1 | vulnerable |
| Ubuntu | libpng1.6 | pro | 1.6.37-2ubuntu0.1~esm2 | vulnerable |
| Ubuntu | libpng1.6 | pro | 1.6.37-2ubuntu0.1~esm3 | fixed |
| Ubuntu | libpng1.6 | 22.04 | 1.6.37-3build4 | vulnerable |
| Ubuntu | libpng1.6 | 22.04 | 1.6.37-3build5 | vulnerable |
| Ubuntu | libpng1.6 | 22.04 | 1.6.37-3ubuntu0.1 | vulnerable |
| Ubuntu | libpng1.6 | 22.04 | 1.6.37-3ubuntu0.3 | vulnerable |
| Ubuntu | libpng1.6 | 22.04 | 1.6.37-3ubuntu0.4 | vulnerable |
| Ubuntu | libpng1.6 | 22.04 | 1.6.37-3ubuntu0.5 | fixed |
| Ubuntu | libpng1.6 | 24.04 | 1.6.40-1 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.40-2 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.40-3 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.42-1 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.43-1 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.43-3 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.43-5build1 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.43-5ubuntu0.1 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.43-5ubuntu0.3 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.43-5ubuntu0.4 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.43-5ubuntu0.5 | vulnerable |
| Ubuntu | libpng1.6 | 24.04 | 1.6.43-5ubuntu0.6 | fixed |
| Ubuntu | libpng1.6 | 25.10 | 1.6.47-1.1 | vulnerable |
| Ubuntu | libpng1.6 | 25.10 | 1.6.48-1 | vulnerable |
| Ubuntu | libpng1.6 | 25.10 | 1.6.49-1~exp1 | vulnerable |
| Ubuntu | libpng1.6 | 25.10 | 1.6.50-1~exp1 | vulnerable |
| Ubuntu | libpng1.6 | 25.10 | 1.6.50-1 | vulnerable |
| Ubuntu | libpng1.6 | 25.10 | 1.6.50-1ubuntu0.1 | vulnerable |
| Ubuntu | libpng1.6 | 25.10 | 1.6.50-1ubuntu0.3 | vulnerable |
| Ubuntu | libpng1.6 | 25.10 | 1.6.50-1ubuntu0.4 | vulnerable |
| Ubuntu | libpng1.6 | 25.10 | 1.6.50-1ubuntu0.5 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | libpng1.6 | source | sid | 1.6.56-1 | not yet assigned | Not reported | [1132013] |
| Debian | libpng1.6 | source | forky | 1.6.56-1 | not yet assigned | Not reported | [1132013] |
| Debian | libpng1.6 | source | trixie | 1.6.48-1+deb13u4 | not yet assigned | Not reported | [1132013] |
| Debian | libpng1.6 | source | bookworm | 1.6.39-2+deb12u4 | not yet assigned | Not reported | [1132013] |
| Cpe | libpng1.6 | cpe | Not reported | 1.6.43-5ubuntu0.6 | Not reported | Not reported | Not reported |
| Cpe | libpng-dev | cpe | Not reported | 1.6.43-5ubuntu0.6 | Not reported | Not reported | Not reported |
| Cpe | libpng-tools | cpe | Not reported | 1.6.43-5ubuntu0.6 | Not reported | Not reported | Not reported |
| Cpe | libpng16-16t64 | cpe | Not reported | 1.6.43-5ubuntu0.6 | Not reported | Not reported | Not reported |
| Cpe | libpng | cpe | Not reported | 1.6.56 | Not reported | Not reported | Not reported |
| Android | platform/external/libpng | Android | Not reported | 14:2026-09-01 | Not reported | ASB-A-496616027 | Not reported |
| Alpine | libpng | apk | 3.20 | 1.6.56-r0 | Not reported | ALPINE-CVE-2026-33636 | Not reported |
| Alpine | libpng | apk | 3.21 | 1.6.56-r0 | Not reported | ALPINE-CVE-2026-33636 | Not reported |
| Alpine | libpng | apk | 3.22 | 1.6.56-r0 | Not reported | ALPINE-CVE-2026-33636 | Not reported |
| Alpine | libpng | apk | 3.23 | 1.6.56-r0 | Not reported | ALPINE-CVE-2026-33636 | Not reported |
| Alpine | libpng | apk | 3.24 | 1.6.56-r0 | Not reported | ALPINE-CVE-2026-33636 | Not reported |
| Ubuntu | libpng1.6 | deb | pro | 1.6.37-2ubuntu0.1~esm3 | Not reported | UBUNTU-CVE-2026-33636 | Not reported |
| Ubuntu | libpng1.6 | deb | 22.04 | 1.6.37-3ubuntu0.5 | Not reported | UBUNTU-CVE-2026-33636 | Not reported |
| Ubuntu | libpng1.6 | deb | 24.04 | 1.6.43-5ubuntu0.6 | Not reported | UBUNTU-CVE-2026-33636 | Not reported |
| Ubuntu | libpng1.6 | deb | 25.10 | 1.6.50-1ubuntu0.5 | Not reported | UBUNTU-CVE-2026-33636 | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libpng16-16]Fixed
Source package: [libpng1.6]
Details (4)
1.6.39-2+deb12u5· amd64 · bookwormFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
1.6.39-2+deb12u5· arm64 · bookwormFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
1.6.39-2+deb12u5· amd64 · bookworm-securityFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
1.6.39-2+deb12u5· arm64 · bookworm-securityFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
- [libpng-dev]Fixed
Source package: [libpng1.6]
Details (4)
1.6.39-2+deb12u5· amd64 · bookwormFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
1.6.39-2+deb12u5· arm64 · bookwormFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
1.6.39-2+deb12u5· amd64 · bookworm-securityFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
1.6.39-2+deb12u5· arm64 · bookworm-securityFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
- [libpng-tools]Fixed
Source package: [libpng1.6]
Details (4)
1.6.39-2+deb12u5· amd64 · bookwormFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
1.6.39-2+deb12u5· arm64 · bookwormFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
1.6.39-2+deb12u5· amd64 · bookworm-securityFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
1.6.39-2+deb12u5· arm64 · bookworm-securityFixed · Fixed:
1.6.39-2+deb12u4nvd · libpng1.6 · debian · bookworm; nvd · libpng1.6 · debian · 12
[Debian 13 (Trixie)]
- [libpng16-16t64]Fixed
Source package: [libpng1.6]
Details (5)
1.6.48-1+deb13u5· amd64 · trixieFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u5· arm64 · trixieFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u5· amd64 · trixie-security · Historical versionFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u5· arm64 · trixie-securityFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u6· amd64 · trixie-securityFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
- [libpng-dev]Fixed
Source package: [libpng1.6]
Details (5)
1.6.48-1+deb13u5· amd64 · trixieFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u5· arm64 · trixieFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u5· amd64 · trixie-security · Historical versionFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u5· arm64 · trixie-securityFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u6· amd64 · trixie-securityFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
- [libpng-tools]Fixed
Source package: [libpng1.6]
Details (5)
1.6.48-1+deb13u5· amd64 · trixieFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u5· arm64 · trixieFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u5· amd64 · trixie-security · Historical versionFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u5· arm64 · trixie-securityFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
1.6.48-1+deb13u6· amd64 · trixie-securityFixed · Fixed:
1.6.48-1+deb13u4nvd · libpng1.6 · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/suse-su-2026_23063-1.json]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-33636]
- [https://osv.dev/vulnerability/ALPINE-CVE-2026-33636]
- [https://osv.dev/vulnerability/ASB-A-496616027]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-33636]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2026-33636]
- [https://security-tracker.debian.org/tracker/CVE-2026-33636]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33636.json]
- [https://ubuntu.com/security/notices/USN-8251-1]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-2919.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX] · [Ubuntu Security Notices (USN)]