8.3

CVE-2019-9900: envoyproxy envoy Injection

CVSS: 8.3v3.1HighModified
Published 25-04-2019Last modified 04-08-2024
Open JSON

Vulnerability summary

CVE-2019-9900 is a high (CVSS 8.3) Injection vulnerability in envoyproxy envoy. EPSS estimates a 3.73% chance of exploitation in the next 30 days, higher than 89.7% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
44/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.3/10
010
High · v3.1 (NVD)
EPSS score
3.73%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 1
RHSA-2019:0741

Timeline

  1. 25-04-2019
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

Description

When parsing HTTP/1.x header values, Envoy 1.9.0 and before does not reject embedded zero characters (NUL, ASCII 0x0). This allows remote attackers crafting header values containing embedded NUL characters to potentially bypass header matching rules, gaining access to unauthorized resources.

CVSS metrics

4 scores · 2 sources · 3 versions

EPSS trend

Probability

3.73%

Chance of exploitation in the next 30 days

Percentile

90%

Versus all other CVEs

30-day change

0.00 pp

From 3.73% on 19-09-2026

19-09-202619-10-2026
EPSS score
3.73%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Envoy

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Envoyproxy1 product
Redhat1 product

2 vendors · 2 products

References

5 links