CyberSecBulletin
CVE-2022-22721NVD status: Modified

Apache HTTP Server: Integer Overflow or Wraparound

Published Updated By the CyberSecBulletin desk

CVE-2022-22721 is a critical-severity integer overflow or wraparound vulnerability in Apache HTTP Server from Apache, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Apache HTTP Server versions: Apache HTTP Server 2.4 through 2.4.52. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 41.9% chance of exploitation within 30 days, which is in the top 1.29% of all scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Mac OS X to 10.15.7 or a later version.
  2. Update macOS to 11.6.6 or 12.4, whichever matches your release line, or a later version.
  3. Read the advisory on httpd.apache.org for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache HTTP ServerApache HTTP Server 2.4 through 2.4.52Not stated
ApacheHTTP Server2.4.52 and earlierNot stated
Fedora ProjectFedora34; 35; 36Not stated
DebianDebian Linux9.0Not stated
OracleEnterprise Manager Ops Center12.4.0.0Not stated
OracleZfs Storage Appliance Kit8.8Not stated
AppleMac OS X10.15 up to, but not including, 10.15.7; 10.15.710.15.7
ApplemacOS11.0 up to, but not including, 11.6.6; 12.0 up to, but not including, 12.411.6.6, 12.4

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.1CriticalNVD
CVSS 2.05.8MediumNVD

Official description

If LimitXMLRequestBody is set to allow request bodies larger than 350MB (defaults to 1M) on 32 bit systems an integer overflow happens which later causes out of bounds writes. This issue affects Apache HTTP Server 2.4.52 and earlier.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Integer Overflow or Wraparound

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

How developers prevent this class of flaw

  • Ensure that all protocols are strictly defined, such that all out-of-bounds behavior can be identified simply, and require strict conformance to the protocol.
  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. If possible, choose a language or compiler that performs automatic bounds checking.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Use libraries or frameworks that make it easier to handle numbers without unexpected consequences. Examples include safe integer handling packages such as SafeInt (C++) or IntegerLib (C or C++).

More Integer Overflow or Wraparound vulnerabilities (CWE-190)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Other vulnerabilities in Apache HTTP Server

All Apache HTTP Server vulnerabilities

Recent Integer Overflow or Wraparound vulnerabilities

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