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Fencer Vulns
high 7.5

CVE-2020-1763 json

An out-of-bounds buffer read flaw was found in the pluto daemon of libreswan from versions 3.27 till 3.31 where, an unauthenticated attacke…

published 2020-05-12 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-12590

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
3.6%
EPSS 3.6% chance of exploitation in 30 days, percentile 89%
public exploits
0
none known

Summary

An out-of-bounds buffer read flaw was found in the pluto daemon of libreswan from versions 3.27 till 3.31 where, an unauthenticated attacker could use this flaw to crash libreswan by sending specially-crafted IKEv1 Informational Exchange packets. The daemon respawns after the crash.

Patch / fix

  • libreswan Debian 13, Debian 12 3.32-1

debian advisories DEBIAN-CVE-2020-1763

  • libreswan RHEL 8 3.29-7.el8_2
  • libreswan RHEL 8.1 EUS 3.29-7.el8_1
  • libreswan RHEL 8.0 E4S 3.27-10.el8_0

red hat advisories RHSA-2020:2071RHSA-2020:2070RHSA-2020:2069

  • libreswan Alpine 3.24, Alpine 3.23, Alpine 3.22 +10 more 3.32-r0

alpine advisories ALPINE-CVE-2020-1763

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-1763 updated cvss 7.5

libreswan: DoS attack via malicious IKEv1 informational exchange message

  • Red Hat Enterprise Linux AppStream (v. 8) libreswan 3.29-7.el8_2
    fixed: vendor fix “Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update as soon as possible.” RHSA-2020:2070
  • Red Hat Enterprise Linux AppStream E4S (v. 8.0) libreswan 3.27-10.el8_0
    fixed: vendor fix “Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update as soon as possible.” RHSA-2020:2069
  • Red Hat Enterprise Linux AppStream EUS (v. 8.1) libreswan 3.29-7.el8_1
    fixed: vendor fix “Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update as soon as possible.” RHSA-2020:2071
  • Red Hat Enterprise Linux 6 libreswan Red Hat Enterprise Linux 7 libreswan
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-21-040-04 updated cvss 7.5

Siemens RUGGEDCOM ROX II

  • Siemens RUGGEDCOM ROX MX5000 <V2.14.0 Siemens RUGGEDCOM ROX RX1400 <V2.14.0 Siemens RUGGEDCOM ROX RX1500 <V2.14.0 Siemens RUGGEDCOM ROX RX1501 <V2.14.0 Siemens RUGGEDCOM ROX RX1510 <V2.14.0 Siemens RUGGEDCOM ROX RX1511 <V2.14.0
    +2 more products
    Siemens RUGGEDCOM ROX RX1512 <V2.14.0 Siemens RUGGEDCOM ROX RX5000 <V2.14.0
    affected: fixed in V2.14.0, mitigation

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

Exploit prediction

3.57% chance of exploitation in the next 30 days, higher than 89% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

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

Affected products

  • the libreswan Project libreswan

Classification

Weakness

References

Sources

Fencer Vulns 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.