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Fencer Intel
high 7.5

CVE-2020-11709 json

cpp-httplib through 0.5.8 does not filter \r\n in parameters passed into the set_redirect and set_header functions, which creates possibili…

published 6y ago modified 4mo ago also EUVD-2020-4051

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.7%
EPSS 1.7% chance of exploitation in 30 days, percentile 77%
public exploits
0
none known

Summary

cpp-httplib through 0.5.8 does not filter \r\n in parameters passed into the set_redirect and set_header functions, which creates possibilities for CRLF injection and HTTP response splitting in some specific contexts.

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Exploit prediction

1.68% chance of exploitation in the next 30 days, higher than 77% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/yhirose/cpp-httplib/issues/425 referenced PoC, tagged "exploit" by a source, unverified
  • gist.github.com https://gist.github.com/shouc/a9330df817128bc4c4132abf3de09495 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:P/A:N

Classification

Weakness
  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.