CVSS 3.1
4.3 mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:NCVE-2026-124077 Apache Commons Codec: NUL bytes in tree entry names cause Git/SWHID identifier collisions (GitIdentifiers class)
Medium (4.3) in apache software foundation apache commons codec. EPSS 0.3% estimated probability of exploitation activity in the next 30 days.
On this page
The GitIdentifiers class in Apache Commons Codec did not reject NUL bytes in tree entry names. Because Git uses a NUL byte to mark the end of each entry name in a tree object, a crafted name could make one tree serialize to the same bytes as a different tree. Two different directory trees could then receive the same Git tree identifier or SWHID.
The impact is limited: common file systems do not allow NUL bytes in file names, so trees built by walking a file system are not affected. Only applications that build trees from names supplied by other sources, such as entries of archive formats that permit NUL bytes in names (e.g. ZIP) or names passed directly to the API, are exposed.
This issue affects Apache Commons Codec: from 1.22.0 before 1.23.0.
Users are recommended to upgrade to version 1.23.0, which fixes the issue.
Severity
- EPSS
- 0.3% estimated probability of exploitation activity in the next 30 days; 28th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-12. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-158 Improper Neutralization of Null Byte or NUL Character
- Published
- Modified
- Assigned by
- apache (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
- apache software foundation:apache commons codec
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| Apache Software Foundation Apache Commons Codec | from 1.22.0 before 1.23.0 |
Fix and patched versions
- openSUSE: fixed package versions per release
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | 14.04:LTS, 16.04:LTS, 18.04:LTS and 5 more | libcommons-codec-java | no fix listed | UBUNTU-CVE-2026-124077 |
| openSUSE | Tumbleweed | apache-commons-codec | 1.23.0-1.1 | openSUSE-SU-2026:12523-1 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0; SUSE security data, CC BY 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu · openSUSE.
Attack patterns (CAPEC)
- CAPEC-52 Embedding NULL Bytes Likelihood: High · Severity: High
- CAPEC-53 Postfix, Null Terminate, and Backslash Likelihood: High · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.
History
- Scored 4.3 medium
Changes since this site first stored the record. The same for every record: /api/public/changes.