infinte loop in libpcap before 1.10.7
Published Sep 5, 2026
5.5
MEDIUMCVSS 3.1
EPSS 0.10%
Description
libpcap BPF interpreter treats the offset in the 'ja L' BPF instruction as a signed integer to implement looping via backward jumps, but it does not limit the number of loop iterations. In particular uncommon use cases a crafted filter program can cause the interpreter to loop infinitely.
Affected products
-
- Version 0StatusaffectedConstraints<1.10.7
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| The Tcpdump Group | Libpcap | unaffected |
|
No data.
No data.
Red Hat Enterprise Linux 10
libpcap
Fix deferred
Red Hat Enterprise Linux 6
libpcap
Fix deferred
Red Hat Enterprise Linux 7
libpcap
Fix deferred
Red Hat Enterprise Linux 8
libpcap
Fix deferred
Red Hat Enterprise Linux 9
libpcap
Fix deferred
Red Hat OpenShift Container Platform 4
openshift/ose-rhel-coreos-8
Fix deferred
Red Hat OpenShift Container Platform 4
openshift/ose-rhel-coreos-9
Fix deferred
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | libpcap | Fix deferred | n/a |
| Red Hat Enterprise Linux 6 | libpcap | Fix deferred | n/a |
| Red Hat Enterprise Linux 7 | libpcap | Fix deferred | n/a |
| Red Hat Enterprise Linux 8 | libpcap | Fix deferred | n/a |
| Red Hat Enterprise Linux 9 | libpcap | Fix deferred | n/a |
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-8 | Fix deferred | n/a |
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-9 | Fix deferred | n/a |
No package ranges for this CVE.
Remediation
Vendor solution
Upgrade to libpcap 1.10.7.
Red Hat statement
This Moderate impact flaw in libpcap's BPF interpreter could lead to a denial of service. Exploitation requires a local attacker with low privileges to provide a specially crafted filter program, causing an infinite loop and resource exhaustion. This limits the attack surface to specific, uncommon use cases where arbitrary BPF filters can be supplied.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
PartialDecision
n/aAssessed Sep 8, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
Sep–Oct 2026- EPSS v5
Percentile over time
- EPSS v5
Table of values (2 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.10% (0.00105) | 0.99th | v5 (v2026.06.15) |
| Sep 6, 2026 | 0.10% (0.00098) | 0.85th | v5 (v2026.06.15) |
References (5)
- https://access.redhat.com/security/cve/CVE-2026-6554 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2529091 Issue Tracking
- https://github.com/the-tcpdump-group/libpcap/commit/ff3c83475ac303c6b681c52ad0b6e14795a8e0ce patch
- https://nvd.nist.gov/vuln/detail/CVE-2026-6554
- https://www.cve.org/CVERecord?id=CVE-2026-6554
Change history (0)
No recorded changes yet.