CVE-2020-13112
📋 TL;DR
This vulnerability in libexif allows attackers to read beyond allocated memory buffers when processing EXIF MakerNote data, potentially exposing sensitive information or causing application crashes. It affects any software using vulnerable versions of libexif for image metadata processing. The impact is particularly significant for applications that process untrusted image files.
💻 Affected Systems
- libexif
- Applications using libexif (image viewers, editors, web apps)
📦 What is this software?
Leap by Opensuse
Libexif by Libexif Project
Ubuntu Linux by Canonical
Ubuntu Linux by Canonical
Ubuntu Linux by Canonical
Ubuntu Linux by Canonical
Ubuntu Linux by Canonical
Ubuntu Linux by Canonical
⚠️ Risk & Real-World Impact
Worst Case
Information disclosure of sensitive memory contents leading to credential exposure or remote code execution through memory corruption.
Likely Case
Application crashes (denial of service) and potential information leakage from process memory.
If Mitigated
Limited impact with proper input validation and memory protections, though crashes may still occur.
🎯 Exploit Status
Exploitation requires processing a malicious image file with crafted EXIF data.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: libexif 0.6.22 and later
Vendor Advisory: https://github.com/libexif/libexif/commit/435e21f05001fb03f9f186fa7cbc69454afd00d1
Restart Required: Yes
Instructions:
1. Update libexif package to version 0.6.22 or later using your distribution's package manager. 2. Restart affected applications. 3. Recompile any statically linked applications with patched libexif.
🔧 Temporary Workarounds
Disable EXIF processing
allConfigure applications to disable EXIF metadata parsing if not required.
Application-specific configuration required
Input validation
allImplement strict validation of image files before processing.
Use tools like exiftool to validate EXIF data before processing
🧯 If You Can't Patch
- Implement network segmentation to isolate vulnerable systems
- Use application allowlisting to restrict which applications can process image files
🔍 How to Verify
Check if Vulnerable:
Check libexif version: dpkg -l | grep libexif (Debian/Ubuntu) or rpm -qa | grep libexif (RHEL/CentOS)Check Version:
pkg-config --modversion libexifVerify Fix Applied:
Verify libexif version is 0.6.22 or higher: exif --version | head -1📡 Detection & Monitoring
Log Indicators:
- Application crashes with segmentation faults
- Memory access violation errors
Network Indicators:
- Unusual image upload patterns
- Multiple failed image processing attempts
SIEM Query:
source="application.log" AND ("segmentation fault" OR "SIGSEGV") AND process="*image*"🔗 References
- http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00017.html
- https://github.com/libexif/libexif/commit/435e21f05001fb03f9f186fa7cbc69454afd00d1
- https://lists.debian.org/debian-lts-announce/2020/05/msg00025.html
- https://security.gentoo.org/glsa/202007-05
- https://usn.ubuntu.com/4396-1/
- http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00017.html
- https://github.com/libexif/libexif/commit/435e21f05001fb03f9f186fa7cbc69454afd00d1
- https://lists.debian.org/debian-lts-announce/2020/05/msg00025.html
- https://security.gentoo.org/glsa/202007-05
- https://usn.ubuntu.com/4396-1/
