Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2019-6293

20
FAUCET Score

CVE-2019-6293 describes a stack exhaustion vulnerability in flex 2.6.4, specifically within the mark_beginning_as_normal function in nfa.c. This flaw allows remote attackers to trigger a denial-of-service by crafting input with numerous '*' characters, leading to recursive function calls. Rated as MEDIUM severity (CVSS 5.5), it requires local access and user interaction for exploitation, resulting in high availability impact. There is no evidence of active exploitation, publicly available exploit code, or significant community discussion surrounding this vulnerability.

Impacted Technologies

VendorProductVersion(s)CPE
2.6.4CPE matchmatch criteria
cpe:2.3:a:westes:flex:2.6.4:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.0

5.5MEDIUM

CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
Exploitability Score
1.8
Impact Score
3.6
CvssVersion
3.0

Exploit Intelligence

EPSS Score
1.59%
Probability of exploitation in next 30 days
EPSS Percentile
73.1%
Percentile rank of EPSS score among Peer Group
As of 2026-07-26
Model: v2026.06.15
This CVE's current EPSS score of 0.0159 is in the 83rd percentile among its peer group of 5,758 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (45)

microsoftpatch availablevia msrc
Product: flex-devel-2.6.4-7.azl3.aarch64.rpm on Azure Linux 3.0 ARMFixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 17068-16823Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 17069-16817Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 17069-17084Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: flex-2.6.4-7.azl3.aarch64.rpm on Azure Linux 3.0 ARMFixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 17067-16820Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: cm1 flex 2.6.4-6 on CBL Mariner 1.0Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: cbl2 flex 2.6.4-7 on CBL Mariner 2.0Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: azl3 flex 2.6.4-7 on Azure Linux 3.0Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13280-12137Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: 13281-12137Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: 13282-12137Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: 13283-12138Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: 13284-12138Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: 13285-12138Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: 13286-12139Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13287-12139Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13288-12139Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13289-12140Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13290-12140Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13291-12140Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13292-12356Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13293-12356Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13294-12357Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: 13295-12357Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: CBL Mariner 1.0 x64Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: CBL Mariner 1.0 ARMFixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: CBL Mariner 2.0 x64Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: CBL Mariner 2.0 ARMFixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: flex-2.6.4-6.cm1.x86_64.rpm on CBL Mariner 1.0 x64Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: flex-devel-2.6.4-6.cm1.x86_64.rpm on CBL Mariner 1.0 x64Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: flex-debuginfo-2.6.4-6.cm1.x86_64.rpm on CBL Mariner 1.0 x64Fixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: flex-2.6.4-6.cm1.aarch64.rpm on CBL Mariner 1.0 ARMFixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: flex-devel-2.6.4-6.cm1.aarch64.rpm on CBL Mariner 1.0 ARMFixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: flex-debuginfo-2.6.4-6.cm1.aarch64.rpm on CBL Mariner 1.0 ARMFixed in: 2.6.4-6
microsoftpatch availablevia msrc
Product: flex-2.6.4-7.cm2.x86_64.rpm on CBL Mariner 2.0 x64Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: flex-devel-2.6.4-7.cm2.x86_64.rpm on CBL Mariner 2.0 x64Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: flex-debuginfo-2.6.4-7.cm2.x86_64.rpm on CBL Mariner 2.0 x64Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: flex-2.6.4-7.cm2.aarch64.rpm on CBL Mariner 2.0 ARMFixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: flex-devel-2.6.4-7.cm2.aarch64.rpm on CBL Mariner 2.0 ARMFixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: flex-debuginfo-2.6.4-7.cm2.aarch64.rpm on CBL Mariner 2.0 ARMFixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: flex-2.6.4-7.azl3.x86_64.rpm on Azure Linux 3.0 x64Fixed in: 2.6.4-7
microsoftpatch availablevia msrc
Product: flex-devel-2.6.4-7.azl3.x86_64.rpm on Azure Linux 3.0 x64Fixed in: 2.6.4-7
redhatvendor investigatingvia redhat_api
Product: Red Hat Enterprise Linux 7Fixed in: flex
redhatvendor investigatingvia redhat_api
Product: Red Hat Enterprise Linux 8Fixed in: flex

Vendor Advisories (4)

microsoft2024-Jun/CVE-2019-6293

CVE-2019-6293

Jun 11, 2024
microsoft2020-Aug/CVE-2019-6293

CVE-2019-6293

Aug 11, 2020
redhatCVE-2019-6293Low

flex: Recursive calls in the function mark_beginning_as_normal resulting in a denial of service

Jan 9, 2019
microsoft2019-Jan/CVE-2019-6293Moderate

An issue was discovered in the function mark_beginning_as_normal in nfa.c in flex 2.6.4. There is a stack exhaustion problem caused by the mark_beginning_as_normal function making recursive calls to itself in certain scenarios involving lots of '*' characters. Remote attackers could leverage this vulnerability to cause a denial-of-service.

Jan 8, 2019

References

github.com / westes/flex/issues/414
ExploitThird Party Advisory