CVE-2022-27470
📋 TL;DR
CVE-2022-27470 is an arbitrary memory write vulnerability in SDL_ttf library versions 2.0.18 and below. Attackers can exploit this by providing a malicious TTF font file to the TTF_RenderText_Solid() function, potentially leading to remote code execution. Applications using SDL_ttf for font rendering are affected.
💻 Affected Systems
- SDL_ttf library
- Applications using SDL_ttf for font rendering
📦 What is this software?
Fedora by Fedoraproject
Fedora by Fedoraproject
Fedora by Fedoraproject
Sdl Ttf by Libsdl
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with the privileges of the application using SDL_ttf, potentially leading to full system compromise.
Likely Case
Application crash (denial of service) or limited memory corruption leading to information disclosure.
If Mitigated
No impact if the vulnerability is patched or if untrusted TTF files are not processed.
🎯 Exploit Status
Exploitation requires the attacker to supply a crafted TTF file to the vulnerable function. The vulnerability is in a widely used library, making weaponization likely.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: SDL_ttf v2.0.19 and later
Vendor Advisory: https://github.com/libsdl-org/SDL_ttf/commit/db1b41ab8bde6723c24b866e466cad78c2fa0448
Restart Required: Yes
Instructions:
1. Update SDL_ttf to version 2.0.19 or later. 2. Recompile any applications using SDL_ttf with the updated library. 3. Restart affected applications.
🔧 Temporary Workarounds
Disable TTF file processing
allPrevent applications from processing TTF font files from untrusted sources.
Input validation
allImplement strict validation of TTF files before passing them to SDL_ttf functions.
🧯 If You Can't Patch
- Isolate applications using SDL_ttf in restricted environments with minimal privileges.
- Implement network segmentation to limit access to vulnerable applications.
🔍 How to Verify
Check if Vulnerable:
Check SDL_ttf library version: ldd /path/to/application | grep SDL_ttf and check version numbers.Check Version:
pkg-config --modversion SDL2_ttf (Linux) or check library properties in Windows.Verify Fix Applied:
Verify SDL_ttf version is 2.0.19 or later and test with known malicious TTF files.📡 Detection & Monitoring
Log Indicators:
- Application crashes when processing TTF files
- Memory access violation errors in application logs
Network Indicators:
- Unexpected TTF file uploads to applications
- Network traffic patterns indicating font file exploitation attempts
SIEM Query:
source="application.log" AND ("segmentation fault" OR "access violation") AND "TTF"🔗 References
- https://github.com/libsdl-org/SDL_ttf/commit/db1b41ab8bde6723c24b866e466cad78c2fa0448
- https://github.com/libsdl-org/SDL_ttf/issues/187
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EAGMQMRQDTZFQW64JEW3O6HY3JYLAAHT/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RXI3MDPR24W5557G34YHWOP2MOK6BTGB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XPYTEBBNHCDGPVFACC5RC5K2FZUCYTPZ/
- https://github.com/libsdl-org/SDL_ttf/commit/db1b41ab8bde6723c24b866e466cad78c2fa0448
- https://github.com/libsdl-org/SDL_ttf/issues/187
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EAGMQMRQDTZFQW64JEW3O6HY3JYLAAHT/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RXI3MDPR24W5557G34YHWOP2MOK6BTGB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XPYTEBBNHCDGPVFACC5RC5K2FZUCYTPZ/
