CVE-2017-9047

Advisory lineage Upstream: 0 Downstream: 11
Modified
Published: 18 May 2017, 06:13
Last modified:05 Aug 2024, 16:55

Vulnerability Summary

Overall Risk (default)
medium
41/100
CVSS Score
7.5 HIGH
v3.0 (nvd)
EPSS Score
2.66% LOW
3% probability -0.12%
KEV
Not listed
Ransomware
No reports
Public exploits
1 found
Dark Web
Not detected

Timeline

18 May 2017, 06:13
Published
Vulnerability first disclosed
05 Aug 2024, 16:55
Last Modified
Vulnerability information updated

Description

A buffer overflow was discovered in libxml2 20904-GITv2.9.4-16-g0741801. The function xmlSnprintfElementContent in valid.c is supposed to recursively dump the element content definition into a char buffer 'buf' of size 'size'. The variable len is assigned strlen(buf). If the content->type is XML_ELEMENT_CONTENT_ELEMENT, then (i) the content->prefix is appended to buf (if it actually fits) whereupon (ii) content->name is written to the buffer. However, the check for whether the content->name actually fits also uses 'len' rather than the updated buffer length strlen(buf). This allows us to write about "size" many bytes beyond the allocated memory. This vulnerability causes programs that use libxml2, such as PHP, to crash.

CVSS Metrics

  • v3.0•HIGH•Score: 7.5CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
  • v2.0•MEDIUM•Score: 5AV:N/AC:L/Au:N/C:N/I:N/A:P

EPSS Trends

Current EPSS score: 2.66%• Percentile: 86%

Techniques & Countermeasures

  • CWE-119•Improper Restriction of Operations within the Bounds of a Memory Buffer

    The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

Affected Systems

  • xmlsoft•libxml2

    2.9.4

References (6)