CVE-2017-16803

In Libav through 11.11 and 12.x through 12.1, the smacker_decode_tree function in libavcodec/smacker.c does not properly restrict tree recursion, which allows remote attackers to cause a denial of service (bitstream.c:build_table() out-of-bounds read and application crash) via a crafted Smacker stream.

Published: 2017-11-13 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-16803 is rated Moderate Risk (62.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 3.01%). EPSS rose +2.33% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-16803

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.68% 3.01% +2.33%
2 2025-03-30 1.25% 0.68% -0.57%
3 2025-03-29 — 1.25% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-16803

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2017-16803

OS Trackers for CVE-2017-16803

vendor priority summary link
debian not yet assigned CVE-2017-16803 not yet assigned priority: Debian including 1 source packages (ffmpeg), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-16803
gentoo normal CVE-2017-16803: 1 GLSA(s) (201811-19), 1 atom(s) (media-video/libav); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2017-16803
ubuntu medium CVE-2017-16803 medium priority: Ubuntu including 1 source packages (libav), 17 status rows across 17 suites (artful, bionic, cosmic, disco, focal, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial, zesty): DNE 15, needed 1, released 1. https://ubuntu.com/security/CVE-2017-16803

Affected software / configurations for CVE-2017-16803

Vendor Product Version Raw CPE
libav libav <= 11.11 cpe:2.3:a:libav:libav:*:*:*:*:*:*:*:*
libav libav 12.0 cpe:2.3:a:libav:libav:12.0:*:*:*:*:*:*:*
libav libav 12.1 cpe:2.3:a:libav:libav:12.1:*:*:*:*:*:*:*

References for CVE-2017-16803

cvelogic Threat Intelligence