Debian: Security Advisory (DLA-2334-1)

# SPDX-FileCopyrightText: 2020 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.892334");
  script_cve_id("CVE-2020-7663");
  script_tag(name:"creation_date", value:"2020-08-20 05:27:57 +0000 (Thu, 20 Aug 2020)");
  script_version("2024-02-02T05:06:07+0000");
  script_tag(name:"last_modification", value:"2024-02-02 05:06:07 +0000 (Fri, 02 Feb 2024)");
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_tag(name:"severity_vector", value:"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2020-06-04 16:45:45 +0000 (Thu, 04 Jun 2020)");

  script_name("Debian: Security Advisory (DLA-2334-1)");
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2020 Greenbone AG");
  script_family("Debian Local Security Checks");
  script_dependencies("gather-package-list.nasl");
  script_mandatory_keys("ssh/login/debian_linux", "ssh/login/packages", re:"ssh/login/release=DEB9");

  script_xref(name:"Advisory-ID", value:"DLA-2334-1");
  script_xref(name:"URL", value:"https://www.debian.org/lts/security/2020/DLA-2334-1");
  script_xref(name:"URL", value:"https://wiki.debian.org/LTS");

  script_tag(name:"summary", value:"The remote host is missing an update for the Debian 'ruby-websocket-extensions' package(s) announced via the DLA-2334-1 advisory.");

  script_tag(name:"vuldetect", value:"Checks if a vulnerable package version is present on the target host.");

  script_tag(name:"insight", value:"It was discovered that there was a denial of service vulnerability in ruby-websocket-extensions, a library for managing long-lived HTTP 'WebSocket' connections.

The parser took quadratic time when parsing a header containing an unclosed string parameter value whose content is a repeating two-byte sequence. This could be abused by an attacker to conduct a Regex Denial Of Service (ReDoS) on a single-threaded server by providing a malicious payload in the Sec-WebSocket-Extensions HTTP header.

CVE-2020-7663

websocket-extensions ruby module prior to 0.1.5 allows Denial of Service (DoS) via Regex Backtracking. The extension parser may take quadratic time when parsing a header containing an unclosed string parameter value whose content is a repeating two-byte sequence of a backslash and some other character. This could be abused by an attacker to conduct Regex Denial Of Service (ReDoS) on a single-threaded server by providing a malicious payload with the Sec-WebSocket-Extensions header.

For Debian 9 Stretch, these problems have been fixed in version 0.1.2-1+deb9u1.

We recommend that you upgrade your ruby-websocket-extensions packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: [link moved to references]");

  script_tag(name:"affected", value:"'ruby-websocket-extensions' package(s) on Debian 9.");

  script_tag(name:"solution", value:"Please install the updated package(s).");

  script_tag(name:"solution_type", value:"VendorFix");
  script_tag(name:"qod_type", value:"package");

  exit(0);
}

include("revisions-lib.inc");
include("pkg-lib-deb.inc");

release = dpkg_get_ssh_release();
if(!release)
  exit(0);

res = "";
report = "";

if(release == "DEB9") {

  if(!isnull(res = isdpkgvuln(pkg:"ruby-websocket-extensions", ver:"0.1.2-1+deb9u1", rls:"DEB9"))) {
    report += res;
  }

  if(report != "") {
    security_message(data:report);
  } else if(__pkg_match) {
    exit(99);
  }
  exit(0);
}

exit(0);