CVE-2019-9900

highpriority · track · 34EPSS 0.037 · 90 %ileEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
3.73% (90th) EPSS
CVSS 7.5 · high
Is it mine?
6 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • Fixedservicemesh-proxy-0:0.9.1-1.el7.src as a component of Red Hat OpenShift Service Mesh 0 Tech Previewredhat_csaf

    Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258

    https://access.redhat.com/errata/RHSA-2019:0741
  • Fixedservicemesh-proxy-0:0.9.1-1.el7.x86_64 as a component of Red Hat OpenShift Service Mesh 0 Tech Previewredhat_csaf

    Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258

    https://access.redhat.com/errata/RHSA-2019:0741
02

cvss

Technical severity, 0–10. One row per scoring source.

8.3
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.5–8.3

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4
v3.18.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:Lprimary · NVD / NIST USexploitability 3.9 · impact 3.7
v3.06.5mediumCVSS:3.0/AC:H/AV:N/A:L/C:L/I:L/PR:N/S:C/UI:Nsecondary · ENISA EU
v3.06.5mediumCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:Lsecondary · cve@mitre.org USexploitability 2.2 · impact 3.7
v3.08.3highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:Lsecondary · Red Hat Product Security US
v3.18.3highAV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:Lsecondary · FSTEC (BDU) RU
v3.17.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L/E:Usecondary · CVSS-BT (t0sche)
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-74USprimaryCWE-20USCWE-20US
04

affected products (6)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • RHSA-2019:0741Red Hat Security Advisory: Istio-Proxy Security Update2019-04-10csaf · redhat_csafUS

    An update for Istio-Proxy is now available for Red Hat OpenShift Service Mesh Tech Preview 0.9.0. Red Hat Product Security has rated this update as having a security impact of important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

06

also known as (4)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bdunvdredhat_csafNVDCVE.orgMITRE
published 2019-04-25modified 2026-06-17
09

references (18)

External citations — patches, advisories, analysis.

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