CVE-2026-28753 (GCVE-0-2026-28753)

Vulnerability from cvelistv5 – Published: 2026-03-24 14:13 – Updated: 2026-03-24 15:24
VLAI
Title
NGINX ngx_mail_proxy_module vulnerability
Summary
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_module module due to the improper handling of CRLF sequences in DNS responses. This allows an attacker-controlled DNS server to inject arbitrary headers into SMTP upstream requests, leading to potential request manipulation. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
Assigner
f5
References
Impacted products
Vendor Product Version
F5 NGINX Open Source Affected: 1.29.0 , < 1.29.7 (semver)
Affected: 0.6.27 , < 1.28.3 (semver)
Create a notification for this product.
F5 NGINX Plus Affected: R36 , < R36 P3 (custom)
Affected: R35 , < R35 P2 (custom)
Affected: R34 , < * (custom)
Affected: R33 , < * (custom)
Affected: R32 , < R32 P5 (custom)
Create a notification for this product.
Date Public
2026-03-24 14:00
Credits
Asim Viladi Oglu Manizada Colin Warren Xiao Liu (Yunnan University) Yuan Tan (UC Riverside) Bird Liu (Lanzhou University)
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.