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No exploitation reportedFix available

CVE-2020-12762

No exploitation reported by the sources we read.

  • Published2020-05-09
  • WeaknessCWE-190 · CWE-787

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

json-c through 0.14 has an integer overflow and out-of-bounds write via a large JSON file, as demonstrated by printbuf_memappend.

Timeline

dates in UTC
  1. 2020-05-0918:15CVE publishedNVD

Versions per branch

NVD
Canonical ubuntu linux
BranchAffectedFixed in
12.4= 12.04no fix published
14.4= 14.04no fix published
16.4= 16.04no fix published
18.4= 18.04no fix published
19.10= 19.10no fix published
20.4= 20.04no fix published
Debian debian linux
BranchAffectedFixed in
8.0= 8.0no fix published
9.0= 9.0no fix published
10.0= 10.0no fix published
Fedoraproject fedora
BranchAffectedFixed in
30.x= 30no fix published
31.x= 31no fix published
32.x= 32no fix published

2 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • json-cUbuntu:Pro:14.04:LTSall versions · fixed in 0.11-3ubuntu1.2+esm3
  • json-cUbuntu:Pro:14.04:LTSall versions · fixed in 0.11-3ubuntu1.2+esm1
  • json-cUbuntu:20.04:LTSall versions · fixed in 0.13.1+dfsg-7ubuntu0.3
  • json-cUbuntu:20.04:LTSall versions · fixed in 0.13.1+dfsg-7ubuntu0.1
  • json-cUbuntu:18.04:LTSall versions · fixed in 0.12.1-1.3ubuntu0.3
  • json-cUbuntu:18.04:LTSall versions · fixed in 0.12.1-1.3ubuntu0.1
  • json-cUbuntu:16.04:LTSall versions · fixed in 0.11-4ubuntu2.6
  • json-cUbuntu:16.04:LTSall versions · fixed in 0.11-4ubuntu2.1

110 more package ranges on OSV.dev

Vendor advisories

  • CVE-2020-12762 Red Hat Product Security140 products fixed · 7 known affected

    libfastjson: integer overflow and out-of-bounds write via a large JSON file

    json-c-devel as a component of Red Hat Enterprise Linux 6 · json-c-doc as a component of Red Hat Enterprise Linux 6 · json-c.src as a component of Red Hat Enterprise Linux 6 · +4 more

  • SSA-202008 Siemens ProductCERT11 known affected

    SSA-202008: Multiple Vulnerabilities in Ruggedcom Rox Before V2.17.0

    RUGGEDCOM ROX MX5000 · RUGGEDCOM ROX MX5000RE · RUGGEDCOM ROX RX1400 · +8 more

  • RHSA-2024:1154 Red Hat Product Security16 products fixed

    Red Hat Security Advisory: libfastjson security update

  • RHSA-2024:1086 Red Hat Product Security16 products fixed

    Red Hat Security Advisory: libfastjson security update

  • RHSA-2024:0573 Red Hat Product Security16 products fixed

    Red Hat Security Advisory: libfastjson security update

  • RHSA-2024:0411 Red Hat Product Security16 products fixed

    Red Hat Security Advisory: libfastjson security update

9 more advisories

Full record on NVD

Fix

  1. Vendor fix Siemens ProductCERT SSA-202008 · 11 productsUpdate to V2.17.0 or later version
  2. Vendor fix Red Hat Product Security RHSA-2024:1154 · 16 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
  3. Vendor fix CISA ICSA-23-348-10 · 5 productsUpdate to V3.1.5 or later version
  4. Vendor fix Siemens ProductCERT SSA-398330 · 1 productUpdate to V3.1.5 or later version
  5. Vendor fix Siemens ProductCERT SSA-794697 · 1 productUpdate to V1.1 or later version
  6. Vendor fix CISA ICSA-23-166-11 · 1 productUpdate to V1.1 or later version

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Published
2020-05-09
Last Modified
2026-10-14
NVD status
Modified
GitHub Advisory
GHSA-3797-gmjf-45gm

Frequently asked questions

What is CVE-2020-12762?

json-c through 0.14 has an integer overflow and out-of-bounds write via a large JSON file, as demonstrated by printbuf_memappend.

Is CVE-2020-12762 actively exploited?

Active exploitation of CVE-2020-12762 has not been confirmed. Its EPSS score was 1.9% on 2026-11-08, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2020-12762?

CVE-2020-12762 has a CVSS v3 base score of 7.8 (HIGH severity), with vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

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Sources for this record