Description
The rencode package through 1.0.6 for Python allows an infinite loop in typecode decoding (such as via ;\x2f\x7f), enabling a remote attack that consumes CPU and memory.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | python-rencode | 1.0.6-2 | — |
| Debian 13 | python-rencode | 1.0.6-2 | — |
| Debian 12 | python-rencode | 1.0.6-2 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | python-rencode | No fix yet | — |
| Ubuntu 20.04 LTS | python-rencode | No fix yet | — |
| Ubuntu 18.04 LTS | python-rencode | No fix yet | — |
| Ubuntu 16.04 LTS | python-rencode | No fix yet | — |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | py3-rencode | 1.0.6-r7 | — |
| Alpine v3.23 | py3-rencode | 1.0.6-r7 | — |
| Alpine v3.22 | py3-rencode | 1.0.6-r7 | — |
| Alpine v3.21 | py3-rencode | 1.0.6-r7 | — |
| Alpine v3.20 | py3-rencode | 1.0.6-r7 | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | py3-rencode | 1.0.6-r7 | — |
| Alpine v3.18 | py3-rencode | 1.0.6-r7 | — |
| Alpine v3.17 | py3-rencode | 1.0.6-r7 | — |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
GitHub 1 repository
-
itlabbet/CVE-2021-40839 ★ 1 · Dec 13, 2021
Dirty Cow kernel exploit without libcrypt dependency
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | rencode | <= 1.0.6 | — | GHSA-gh8j-2pgf-x458 |
| PyPI | rencode | all versions | — | PYSEC-2021-345 |
References
- https://github.com/aresch/rencode/pull/29
- https://seclists.org/fulldisclosure/2021/Sep/16
- https://github.com/aresch/rencode/commit/572ff74586d9b1daab904c6f7f7009ce0143bb75
- https://pypi.org/project/rencode/#history
- https://security.netapp.com/advisory/ntap-20211008-0001/
- FEDORA-2022-02340931ec vendor-advisory
- FEDORA-2022-1033a2718b vendor-advisory