PatchTheCVECVE-2021-3889: libmobi is vulnerable to Use of Out-of-range Pointer Offset
51
This month
HIGH 8.1UPGRADE
CVE-2021-3889 is a high-severity flaw (CVSS 8.1) affecting libmobi. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
libmobi is vulnerable to Use of Out-of-range Pointer Offset
Why this priority
- High severity
- Public exploit reference
A fixed release or distro patch exists.
Publisher (CNA): huntr.dev · Vendor: libmobi project
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
libmobi project libmobi UPGRADE
Affected: < 0.8
Fixed in: 0.8
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy libmobi || rpm -q libmobi || libmobi --version
2. UPGRADE to 0.8 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade libmobi
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade libmobi
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2021-3889?
libmobi: upgrade to 0.8. Exact commands for each OS are on this page.
Is CVE-2021-3889 being exploited?
CVE-2021-3889 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2021-3889 affect?
CVE-2021-3889 affects libmobi. Severity is high (CVSS 8.1). libmobi is vulnerable to Use of Out-of-range Pointer Offset
How urgent is CVE-2021-3889?
Priority 51/100. High severity; Public exploit reference
Related CVEs
- CVE-2022-2279 MEDIUM 5.5 UPGRADE NULL Pointer Dereference in GitHub repository bfabiszewski/libmobi prior to 0.11.
- CVE-2022-29788 MEDIUM 6.5 UPGRADE libmobi before v0.10 contains a NULL pointer dereference via the component mobi_buffer_getpointer
- CVE-2022-1987 HIGH 8.1 UPGRADE Buffer Over-read in GitHub repository bfabiszewski/libmobi prior to 0.11.
- CVE-2022-1908 HIGH 8.1 UPGRADE Buffer Over-read in GitHub repository bfabiszewski/libmobi prior to 0.11.
- CVE-2022-1907 HIGH 8.1 UPGRADE Buffer Over-read in GitHub repository bfabiszewski/libmobi prior to 0.11.