CVE-2020-6851

Exp

OpenJPEG through 2.3.1 has a heap-based buffer overflow in opj_t1_clbl_decode_processor in openjp2/t1.c because of lack of opj_j2k_update_image_dimensions validation.

Published: 2020-01-13 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-6851 is rated High Exploit Risk (75.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 4.77%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2020-6851

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2020-6851

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 2026-05-30 5.33% 4.77% -0.56%
2 2026-05-28 4.64% 5.33% +0.70%
3 2026-05-27 4.64%

Full EPSS history (20 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-6851

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/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-2020-6851

OS Trackers for CVE-2020-6851

vendor priority summary link
alpine high CVE-2020-6851: 1 source package rows (openjpeg); 55 state rows across 10 repos (3.10-main, 3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 20, open 35. https://security.alpinelinux.org/vuln/CVE-2020-6851
debian not yet assigned CVE-2020-6851 not yet assigned priority: Debian including 1 source packages (openjpeg2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-6851
redhat high https://access.redhat.com/security/cve/CVE-2020-6851
suse high CVE-2020-6851 severity important: SUSE including 39 source package names (0.3.2-1.2:libopenjp2-7-2.3.0-150000.3.5.1, 0.3.32-3.4:libopenjp2-7-2.3.0-150000.3.5.1, …), 269 product×package rows across 91 product lines (Container containers/lmcache-vllm-openai, Container containers/open-webui, … (91 product lines)): Fixed 116, Known Not Affected 97, Will Not Fix 56. https://www.suse.com/security/cve/CVE-2020-6851/
ubuntu medium CVE-2020-6851 medium priority: Ubuntu including 7 source packages (blender, ghostscript, …), 122 status rows across 18 suites (bionic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 39, needs-triage 27, DNE 25, released 17, not-affected 14. https://ubuntu.com/security/CVE-2020-6851

Affected software / configurations for CVE-2020-6851

Vendor Product Version Raw CPE
uclouvain openjpeg <= 2.3.1 cpe:2.3:a:uclouvain:openjpeg:*:*:*:*:*:*:*:*
fedoraproject fedora 30 cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*
fedoraproject fedora 31 cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux_desktop 7.0 cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
redhat enterprise_linux_eus 7.7 cpe:2.3:o:redhat:enterprise_linux_eus:7.7:*:*:*:*:*:*:*
redhat enterprise_linux_eus 8.1 cpe:2.3:o:redhat:enterprise_linux_eus:8.1:*:*:*:*:*:*:*
redhat enterprise_linux_eus 8.2 cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_eus 8.4 cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:*
redhat enterprise_linux_server 7.0 cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.7 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.7:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 8.2 cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 8.4 cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.7 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.7:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.2 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.4 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.4:*:*:*:*:*:*:*
redhat enterprise_linux_workstation 7.0 cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
oracle georaster 18c cpe:2.3:a:oracle:georaster:18c:*:*:*:*:*:*:*
oracle outside_in_technology 8.5.4 cpe:2.3:a:oracle:outside_in_technology:8.5.4:*:*:*:*:*:*:*
oracle outside_in_technology 8.5.5 cpe:2.3:a:oracle:outside_in_technology:8.5.5:*:*:*:*:*:*:*

References for CVE-2020-6851

URL Tags
https://access.redhat.com/errata/RHSA-2020:0262 Third Party Advisory
https://access.redhat.com/errata/RHSA-2020:0274 Third Party Advisory
https://access.redhat.com/errata/RHSA-2020:0296 Third Party Advisory
https://github.com/uclouvain/openjpeg/issues/1228 Exploit Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/01/msg00025.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/07/msg00008.html Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LACIIDDCKZJEPKTTFILSOSBQL7L3FC6V/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XBRMI2D3XPVWKE3V52KRBW7BJVLS5LD3/
https://www.debian.org/security/2021/dsa-4882 Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2020.html Patch Third Party Advisory
cvelogic Threat Intelligence