CyberSecBulletin
CVE-2023-4863Exploited in the wildNVD status: Analyzed

Google Chromium WebP Heap-Based Buffer Overflow

CVE-2023-4863 is a high-severity out-of-bounds write vulnerability in Chrome from Google, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 116.0.5845.187 as the first without the flaw, so updating Chrome to that release or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on September 13, 2023, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Chrome to 116.0.5845.187 or a later version.
  2. Update libwebp to 1.3.2 or a later version.
  3. Update Firefox to 102.15.1 or 117.0.1 or 115.2.1, whichever matches your release line, or a later version.
  4. CISA's required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
  5. Read the advisory on chromereleases.googleblog.com for workarounds and exact fixed builds.
  6. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  7. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
GoogleChrome116.0.5845.187 up to, but not including, 116.0.5845.187116.0.5845.187
Googlelibwebp1.3.2 up to, but not including, 1.3.21.3.2
Fedora ProjectFedora37; 38; 39Not stated
DebianDebian Linux10.0; 11.0; 12.0Not stated
MozillaFirefoxbefore 102.15.1; before 117.0.1; 115.1.0 up to, but not including, 115.2.1102.15.1, 117.0.1, 115.2.1
MozillaThunderbirdbefore 102.15.1; 115.0 up to, but not including, 115.2.2102.15.1, 115.2.2
MicrosoftEdge Chromiumbefore 116.0.1938.81116.0.1938.81
MicrosoftTeamsbefore 1.6.00.26463; before 1.6.00.264741.6.00.26463, 1.6.00.26474
MicrosoftWebp Image Extensionbefore 1.0.62681.01.0.62681.0
NetAppActive Iq Unified ManagerNot specified in the recordNot stated
BentleySeequent Leapfrogbefore 2023.22023.2
BandisoftHoneyviewbefore 5.515.51

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
RequiredA user must take an action such as opening a file or link.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
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:R/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighNVD
CVSS 3.18.8HighCISA (ADP)

Official description

Heap buffer overflow in libwebp in Google Chrome prior to 116.0.5845.187 and libwebp 1.3.2 allowed a remote attacker to perform an out of bounds memory write via a crafted HTML page. (Chromium security severity: Critical)

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

The underlying weakness: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other references

Other vulnerabilities in Chrome

All Chrome vulnerabilities

Recent Out-of-bounds Write vulnerabilities

Spotted an error? Tell us.