CVE-2020-11993: apache http_server
Vulnerability summary
CVE-2020-11993 is a high (CVSS 7.5) vulnerability in apache http_server. EPSS estimates a 56.45% chance of exploitation in the next 30 days, higher than 99% of scored vulnerabilities. 1 public exploit is recorded.
Public exploit (reference, Date unknown)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 13 · Related 8Timeline
- 07-08-2020PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
Apache HTTP Server versions 2.4.20 to 2.4.43 When trace/debug was enabled for the HTTP/2 module and on certain traffic edge patterns, logging statements were made on the wrong connection, causing concurrent use of memory pools. Configuring the LogLevel of mod_http2 above "info" will mitigate this vulnerability for unpatched servers.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
56.45%
Chance of exploitation in the next 30 days
Percentile
99%
Versus all other CVEs
30-day change
No change 0.00 pp
From 56.45% 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
1 foundExploit Reference (packetstormsecurity.com)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Oracle7 products
- communications_element_manager≥ 8.2.0, ≤ 8.2.2
- communications_session_report_manager≥ 8.2.0, ≤ 8.2.2
- communications_session_route_manager≥ 8.2.0, ≤ 8.2.2
- enterprise_manager_ops_center12.4.0.0
- hyperion_infrastructure_technology11.1.2.4
Debian2 products
- apache2< 2.4.46-1
- debian_linuxEOL10.0
Alpine1 product
- apache2< 2.4.46-r0
Apache1 product
- http_server≥ 2.4.20, < 2.4.44
Canonical1 product
- ubuntu_linuxEOL16.04 | 18.04 | 20.04
Fedoraproject1 product
- fedoraEOL31 | 32
Netapp1 product
Opensuse1 product
- leapEOL15.1 | 15.2
Ubuntu1 product
- apache2< 2.4.29-1ubuntu4.14 | < 2.4.41-4ubuntu3.1
9 vendors · 16 products
References
33 links- lists.opensuse.org/opensuse-security-announce/2020-08/msg00068.htmlVendor AdvisoryX Refsource SUSEMailing ListThird Party Advisory
- lists.opensuse.org/opensuse-security-announce/2020-08/msg00071.htmlVendor AdvisoryX Refsource SUSEMailing ListThird Party Advisory
Show all 33 references
- lists.opensuse.org/opensuse-security-announce/2020-10/msg00081.htmlVendor AdvisoryX Refsource SUSEMailing ListThird Party Advisory
- packetstormsecurity.com/files/160393/Apache-2-HTTP2-Module-Concurrent-Pool-Usage.htmlX Refsource MISCExploitThird Party AdvisoryVDB Entry
