# CVE-2026-4539: python-Pygments: Denial of Service via inefficient regular expression processing in AdlLexer (bsc#1260796).

CVE-2026-4539 is fixed in 3 products on 1 platform, first by DEBIAN-CVE-2026-4539, released March 22, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-4539
- Priority: Routine
- CVSS: n/a (low)
- EPSS: 0.0016
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 22, 2026

## Description

Denial of Service via inefficient regular expression processing in AdlLexer (bsc#1260796).

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | pygments Debian 14 | 2.20.0+dfsg-1 | [DEBIAN-CVE-2026-4539](https://patchblox.com/security/data/fix/linux/debian-cve-2026-4539.md) | Mar 22, 2026 |
| Linux | python-Pygments opensuse-leap 16.0 | 2.19.1-160000.3.1 | [OPENSUSE-SU-2026:20931-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20931-1.md) | Jun 9, 2026 |
| Linux | python-Pygments sles 16.0 | 2.19.1-160000.3.1 | [SUSE-SU-2026:22093-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22093-1.md) | Jun 9, 2026 |
| Linux | python3-pygments amzn 2023 | 2.7.4-1.amzn2023.0.3 | [ALAS2023-2026-1973](https://patchblox.com/security/data/fix/linux/alas2023-2026-1973.md) | Jul 20, 2026 |

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Data as of 2026-11-11T07:45:43Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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