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Public proof of conceptFix available

CVE-2020-8165

A public proof of concept exists; no exploitation attested.

  • Published2020-06-19
  • WeaknessCWE-502

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

A deserialization of untrusted data vulnernerability exists in rails < 5.2.4.3, rails < 6.0.3.1 that can allow an attacker to unmarshal user-provided objects in MemCacheStore and RedisCacheStore potentially resulting in an RCE.

Timeline

dates in UTC
  1. 2020-06-1918:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-11-03 15:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-8165?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-8165?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV
Debian debian linux
BranchAffectedFixed in
8.0= 8.0no fix published
9.0= 9.0no fix published
10.0= 10.0no fix published
Ruby on Rails
BranchAffectedFixed in
6.0≥ 6.0.0, < 6.0.3.16.0.3.1
5.2< 5.2.4.35.2.4.3
5.x≥ 5.0.0, < 5.2.4.35.2.4.3
Opensuse leap
BranchAffectedFixed in
15.1= 15.1no fix published
15.2= 15.2no fix published

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

  • ansible-collection-redhat-satelliteRed Hat:satellite:6.9::el7all versions · fixed in 0:2.0.1-1.el7sat
  • ansible-collection-redhat-satelliteRed Hat:satellite_capsule:6.9::el7all versions · fixed in 0:2.0.1-1.el7sat
  • ansible-runnerRed Hat:satellite:6.9::el7all versions · fixed in 0:1.4.6-1.el7arand 1 other package
  • ansible-runnerRed Hat:satellite_capsule:6.9::el7all versions · fixed in 0:1.4.6-1.el7arand 1 other package
  • ansiblerole-insights-clientRed Hat:satellite:6.9::el7all versions · fixed in 0:1.7.1-1.el7sat
  • ansiblerole-insights-clientRed Hat:satellite_capsule:6.9::el7all versions · fixed in 0:1.7.1-1.el7sat
  • ansiblerole-satellite-receptor-installerRed Hat:satellite:6.9::el7all versions · fixed in 0:0.6.13-1.el7sat
  • ansiblerole-satellite-receptor-installerRed Hat:satellite_capsule:6.9::el7all versions · fixed in 0:0.6.13-1.el7sat

572 more package ranges on OSV.dev

Vendor advisories

  • CVE-2020-8165 Red Hat Product Security1,445 products fixed · 9 known affected

    rubygem-activesupport: potentially unintended unmarshalling of user-provided objects in MemCacheStore and RedisCacheStore

    cfme-gemset as a component of CloudForms Management Engine 5 · cfme-gemset.src as a component of CloudForms Management Engine 5 · system as a component of Red Hat 3scale API Management Platform 2 · +6 more

  • RHSA-2021:1313 Red Hat Product Security1,445 products fixed

    Red Hat Security Advisory: Satellite 6.9 Release

Full record on NVD

Fix

  1. Vendor fix Red Hat Product Security RHSA-2021:1313 · 1,445 productsBefore applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
  2. Workaround from the vendor Red Hat Product Security RHSA-2021:1313 · 1,445 productsRed Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update as soon as possible.
  3. No fix available, says the vendor Red Hat Product Security CVE-2020-8165 · 6 productsFix deferred
  4. No fix available, says the vendor Red Hat Product Security CVE-2020-8165 · 1 productAffected
  5. No fix planned, says the vendor Red Hat Product Security CVE-2020-8165 · 2 productsWill not fix

Advisories and patches

Detection

read 2026-11-02 22:42 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
7 repositories, unverifiedmasahiro331/CVE-2020-8165umiterkol/CVE-2020-8165--Auto-Shelltaipansec/CVE-2020-8165hybryx/CVE-2020-8165AssassinUKG/CVE-2020-8165
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

  • NVDCVSS 3.19.8read 2026-10-23
  • NVDCVSS 2.07.5read 2026-10-23
  • CNAweakness (CWE)CWE-502known since 2026-10-23
  • NVDweakness (CWE)CWE-502read 2026-10-23
  • FIRST EPSSEPSS score45.7 %read 2026-11-02
  • PoC-in-GitHubproof of concept7read 2026-11-02
  • OSVaffected packages—
  • GitHub AdvisoriesadvisoryCRITICAL2020-05-26

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
2020-06-19
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-2p68-f74v-9wc6

Frequently asked questions

What is CVE-2020-8165?

A deserialization of untrusted data vulnernerability exists in rails < 5.2.4.3, rails < 6.0.3.1 that can allow an attacker to unmarshal user-provided objects in MemCacheStore and RedisCacheStore potentially resulting in an RCE.

Is CVE-2020-8165 actively exploited?

Active exploitation of CVE-2020-8165 has not been confirmed. Its EPSS score was 45.7% on 2026-11-03, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2020-8165?

CVE-2020-8165 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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