Malicious PDF — malware analysis report

Static analysis result for SHA-256 1bfb7ca0a4ea91ec…

MALICIOUS

PDF

9.2 KB
MD5: e1e9a251ea7594fd866e70fe261a2108 SHA-1: af1c1c4d855ce98ca37d5944a1bc6285e3be4c39 SHA-256: 1bfb7ca0a4ea91ecfc7c83ab61b9fc6908366cfb0cca1feb4279cf993a794523
178 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious Link

The file is a PDF containing embedded JavaScript, which is flagged as malicious by ClamAV (Pdf.Exploit.Agent-35905). Critical heuristics indicate the exploitation of CVE-2007-5659 via the Collab.collectEmailInfo method, which involves decoding and evaluating JavaScript. The presence of multiple deobfuscated JavaScript files suggests a multi-stage execution process aimed at delivering a payload.

Heuristics 6

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-35905 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35905
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
d8a6b4ad1abf04d0c4a4f89535cfb57f7312edef25c443f4e844c8ec9d0929dd
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 352 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
9e1bc6a80a23be89353d273ffc0e3203f1703b7b3ee72f597666f80d68c0699a
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 11628 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
220d08c2cb9346af5edf125dca9cfc64388cf5dfdaffd0a92747f1f92980cf19
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 4895 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).