# CVE-2011-1929: Denial of service in n/a

> Remote attackers can crash the Dovecot mail server or corrupt mailboxes by sending crafted emails with null characters in headers.

- **Severity:** Medium 5.0 (`AV:N/AC:L/Au:N/C:N/I:N/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 May 2011
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2011-1929, DSA-2252-1, GHSA-8hm3-4p5h-mv6g, RHSA-2011:1187

## What is CVE-2011-1929?

CVE-2011-1929 is a medium-severity denial of service vulnerability in Dovecot Dovecot, published on 24 May 2011. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

lib-mail/message-header-parser.c in Dovecot 1.2.x before 1.2.17 and 2.0.x before 2.0.13 does not properly handle '\0' characters in header names, which allows remote attackers to cause a denial of service (daemon crash or mailbox corruption) via a crafted e-mail message.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2011-1929?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `dovecot` | Red Hat:enterprise_linux:4::as | All versions | 0:0.99.11-10.EL4 |
| `dovecot-debuginfo` | Red Hat:enterprise_linux:4::as | All versions | 0:0.99.11-10.EL4 |
| `dovecot` | Red Hat:enterprise_linux:4::desktop | All versions | 0:0.99.11-10.EL4 |
| `dovecot-debuginfo` | Red Hat:enterprise_linux:4::desktop | All versions | 0:0.99.11-10.EL4 |
| `dovecot` | Red Hat:enterprise_linux:4::es | All versions | 0:0.99.11-10.EL4 |
| `dovecot-debuginfo` | Red Hat:enterprise_linux:4::es | All versions | 0:0.99.11-10.EL4 |
| `dovecot` | Red Hat:enterprise_linux:4::ws | All versions | 0:0.99.11-10.EL4 |
| `dovecot-debuginfo` | Red Hat:enterprise_linux:4::ws | All versions | 0:0.99.11-10.EL4 |
| `dovecot` | Red Hat:enterprise_linux:5::client_workstation | All versions | 0:1.0.7-7.el5_7.1 |
| `dovecot-debuginfo` | Red Hat:enterprise_linux:5::client_workstation | All versions | 0:1.0.7-7.el5_7.1 |
| `dovecot` | Red Hat:enterprise_linux:5::server | All versions | 0:1.0.7-7.el5_7.1 |
| `dovecot-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:1.0.7-7.el5_7.1 |
| `dovecot` | Red Hat:enterprise_linux:6::server | All versions | 1:2.0.9-2.el6_1.1 |
| `dovecot-debuginfo` | Red Hat:enterprise_linux:6::server | All versions | 1:2.0.9-2.el6_1.1 |
| `dovecot-devel` | Red Hat:enterprise_linux:6::server | All versions | 1:2.0.9-2.el6_1.1 |
| `dovecot-mysql` | Red Hat:enterprise_linux:6::server | All versions | 1:2.0.9-2.el6_1.1 |
| `dovecot-pgsql` | Red Hat:enterprise_linux:6::server | All versions | 1:2.0.9-2.el6_1.1 |
| `dovecot-pigeonhole` | Red Hat:enterprise_linux:6::server | All versions | 1:2.0.9-2.el6_1.1 |

Products: Dovecot Dovecot.

## How do I fix CVE-2011-1929?

Upgrade to a fixed version.

## Is CVE-2011-1929 being exploited?

There is no known exploitation of CVE-2011-1929 in the wild and no public exploit code.

## Other vulnerabilities in Dovecot Dovecot

- [CVE-2026-24031](https://insights.sbomify.com/CVE-2026-24031/): Auth bypass in OX Dovecot Pro (high 7.7)
- [CVE-2025-59032](https://insights.sbomify.com/CVE-2025-59032/): Denial of service in OX Dovecot Pro (high 7.5)
- [CVE-2026-27858](https://insights.sbomify.com/CVE-2026-27858/): Denial of service in OX Dovecot Pro (high 7.5)
- [CVE-2021-29157](https://insights.sbomify.com/CVE-2021-29157/): Path traversal in n/a (high 7.5)
- [CVE-2020-10957](https://insights.sbomify.com/CVE-2020-10957/): Null dereference in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2011-1929 and fix it if it is affected.

What it is: CVE-2011-1929 is a medium-severity denial of service vulnerability in Dovecot Dovecot, published on 24 May 2011. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2011-1929 in the wild and no public exploit code.

Affected product: Dovecot Dovecot. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2011-1929/ (Markdown: https://insights.sbomify.com/CVE-2011-1929/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2011-1929
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2011-1929
- OSV: https://osv.dev/vulnerability/CVE-2011-1929

---
From sbomify Insights: https://insights.sbomify.com/CVE-2011-1929/
Summaries are generated and may contain mistakes; the official description above is the record.