CVE-2021-3518: debian debian_linux Use After Free
Vulnerability summary
CVE-2021-3518 is a high (CVSS 8.8) Use After Free vulnerability in debian debian_linux. EPSS estimates a 21.86% chance of exploitation in the next 30 days, higher than 97.6% of scored vulnerabilities.
Not severe (CVSS 8.8, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 18 · Related 14Timeline
- 18-05-2021PublishedVulnerability first disclosed.
- 14-10-2026Last modifiedVulnerability information updated.
Description
There's a flaw in libxml2 in versions before 2.9.11. An attacker who is able to submit a crafted file to be processed by an application linked with libxml2 could trigger a use-after-free. The greatest impact from this flaw is to confidentiality, integrity, and availability.
CVSS metrics
6 scores · 5 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- OSV · RubygemsEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS trend
Probability
21.86%
Chance of exploitation in the next 30 days
Percentile
98%
Versus all other CVEs
30-day change
No change 0.00 pp
From 21.86% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.
Netapp7 products
- active_iq_unified_managerna
- clustered_data_ontapna
- clustered_data_ontap_antivirus_connectorna
- hci_h410c_firmwarena
- manageability_software_development_kitna
Oracle6 products
- communications_cloud_native_core_network_function_cloud_native_environment1.10.0
- enterprise_manager_base_platform13.4.0.0 | 13.5.0.0
- enterprise_manager_ops_center12.4.0.0
- mysql_workbench≤ 8.0.26
- peoplesoft_enterprise_peopletools8.58
Debian2 products
- libxml2< 2.9.10+dfsg-6.6
- debian_linuxEOL9.0
Redhat2 products
Alpine1 product
- libxml2< 2.9.9-r5 | < 2.9.10-r5 | < 2.9.10-r6 | < 2.9.10-r7 | < 2.9.11-r0
Fedoraproject1 product
- fedoraEOL33 | 34
RubyGems1 product
- nokogiri< 1.11.4
Ubuntu1 product
- libxml2< 2.9.1+dfsg1-3ubuntu4.13+esm2 | < 2.9.3+dfsg1-1ubuntu0.7+esm1 | < 2.9.4+dfsg1-6.1ubuntu1.4 | < 2.9.10+dfsg-5ubuntu0.20.04.1
Xmlsoft1 product
- libxml2< 2.9.11
9 vendors · 22 products
References
37 links
lists.debian.org/debian-lts-announce/2021/05/msg00008.htmlMailing ListX Refsource MLISTWEBThird Party Advisory- bugzilla.redhat.com/show_bug.cgi?id=1954242X Refsource MISCWEBIssue TrackingPatchThird Party Advisory
