CVE-2017-1000257

Advisory lineage Upstream: 0 Downstream: 12
Modified
Published: 31 Oct 2017, 21:00
Last modified:15 Apr 2026, 21:02

Vulnerability Summary

Overall Risk (default)
high
70/100
CVSS Score
9.1 CRITICAL
v3.1 (nvd)
EPSS Score
0.86% LOW
1% probability -0.23%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

31 Oct 2017, 21:00
Published
Vulnerability first disclosed
15 Apr 2026, 21:02
Last Modified
Vulnerability information updated

Description

An IMAP FETCH response line indicates the size of the returned data, in number of bytes. When that response says the data is zero bytes, libcurl would pass on that (non-existing) data with a pointer and the size (zero) to the deliver-data function. libcurl's deliver-data function treats zero as a magic number and invokes strlen() on the data to figure out the length. The strlen() is called on a heap based buffer that might not be zero terminated so libcurl might read beyond the end of it into whatever memory lies after (or just crash) and then deliver that to the application as if it was actually downloaded.

CVSS Metrics

  • v3.1•CRITICAL•Score: 9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
  • v3.0•CRITICAL•Score: 9.1CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
  • v2.0•MEDIUM•Score: 6.4AV:N/AC:L/Au:N/C:P/I:N/A:P

EPSS Trends

Current EPSS score: 0.86%• Percentile: 75%

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

  • debian•debian_linux

    8.0 | 9.0

  • haxx•libcurl

    ≥ 7.20.0, ≤ 7.56.0

References (8)