CVE-2018-1303: apache software foundation apache http server Out-of-bounds Read
Vulnerability summary
CVE-2018-1303 is a high (CVSS 7.5) Out-of-bounds Read vulnerability in apache software foundation apache http server. EPSS estimates a 69.80% chance of exploitation in the next 30 days, higher than 99.3% of scored vulnerabilities.
Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 70% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 11 · Related 6Timeline
- 26-03-2018PublishedVulnerability first disclosed.
- 17-09-2024Last modifiedVulnerability information updated.
Description
A specially crafted HTTP request header could have crashed the Apache HTTP Server prior to version 2.4.30 due to an out of bound read while preparing data to be cached in shared memory. It could be used as a Denial of Service attack against users of mod_cache_socache. The vulnerability is considered as low risk since mod_cache_socache is not widely used, mod_cache_disk is not concerned by this vulnerability.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
69.80%
Chance of exploitation in the next 30 days
Percentile
99%
Versus all other CVEs
30-day change
No change 0.00 pp
From 69.80% 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, no user interaction (CVSS vector). Other conditions: not stated in public data.
Netapp4 products
Debian2 products
- apache2< 2.4.33-1
- debian_linuxEOL8.0 | 9.0
Alpine1 product
- apache2< 2.4.33-r0
Apache1 product
- http_server≤ 2.4.29
Apache software foundation1 product
- apache http server2.4.5 to 2.4.29
Canonical1 product
- ubuntu_linuxEOL14.04 | 16.04 | 17.10 | 18.04
Ubuntu1 product
- apache2< 2.4.7-1ubuntu4.20 | < 2.4.18-2ubuntu3.8 | < 2.4.29-1ubuntu4.1
7 vendors · 11 products
References
31 links
- support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03909en_usX Refsource CONFIRMThird Party Advisory
Show all 31 references
- www.openwall.com/lists/oss-security/2018/03/24/3Mailing ListX Refsource MLISTThird Party AdvisoryREPORT
- www.tenable.com/security/tns-2019-09X Refsource CONFIRM