Skip to main content

Boteraser | Website and Server Security Solutions

🛡️ CVE-2026-18738

🟡 CVSS 4.7 — Medium ✅ No Known Exploit CWE-1236 NVD
4.7
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Shlink versions 5.0.0 through 5.1.5 contain a CSV formula injection vulnerability that allows unauthenticated remote attackers to plant spreadsheet formulas into exported visit data by supplying malicious values in User-Agent, Referer, or request path headers beginning with formula-triggering characters such as =, +, -, or @. Attackers can craft a single unauthenticated request against any short URL to embed DDE or WEBSERVICE formula payloads into CSV cells, which are then executed on an administrator's client machine when the exported CSV file is opened in a spreadsheet application that evaluates formulas.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. A user must be tricked into taking some action. The scope is changed, meaning a successful attack can affect components beyond the vulnerable one. Rated impact: confidentiality low, integrity none, availability none.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N

  • Attack vector: Network — reachable from anywhere that can route to the service.
  • Attack complexity: Low — the attack works reliably, with no preparation.
  • Privileges required: None — an unauthenticated stranger can try it.
  • User interaction: Required — someone has to click, open or visit something.
  • Scope: Changed — a successful attack reaches components beyond the vulnerable one.
  • Confidentiality impact: Low — limited, and the attacker does not choose what is affected.
  • Integrity impact: None.
  • Availability impact: None.

Weakness class

CVE-2026-18738 is classified as CWE-1236: Improper Neutralization of Formula Elements in a CSV File. Exported values are not neutralised, so a spreadsheet may treat them as formulas when opened.

Affected software

CVE-2026-18738 is recorded against 1 package.

  • unknown

Timeline and source

Published on 3 August 2026 and last revised on 4 August 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

github.com
github.com
www.vulncheck.com

Other advisories for this package

unknown has other advisories on record. If you are patching this one, these are worth checking on the same host:

Same weakness in other software

These advisories are the same class of weakness (CWE-1236: Improper Neutralization of Formula Elements in a CSV File) in other software:

Details

Severity MEDIUM
CVSS Score 4.7
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
CWE CWE-1236
Public Exploit ✅ No
Source NVD
Published 2026-08-03
Updated 2026-08-20
Modified 2026-08-04
Fix URL N/A

Affected Packages

Software From version Fixed in
unknown — —

Similar Threats

Vulnerability Monitoring

Track new vulnerabilities in the affected software

CVE-2026-18738 is rated CVSS 4.7 Medium. BotEraser monitors your WordPress installation and notifies you when software you use appears in our vulnerability database.

Set Up Free Alerts →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

Browse related advisories

All advisoriesCVECVE 2026
✓