Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2451c07b7a05a96…

MALICIOUS

PDF

60.8 KB Created: 2021-01-02 14:01:34 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: 068d5c020d01dec539de66b2d00cb463 SHA-1: d4461dfe19f68dd9dae0fa94c15fc19214a7bcf3 SHA-256: b2451c07b7a05a966e9fee734cc2e33e4ca12f3ef476f44b4a31bc7926edb0b4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, identified as a link farm, pointing to various PDF files hosted on external domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or distributing further malware. The primary attack pattern involves directing users to these external URLs, which are the highest priority IOCs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://trafffi.ru/123?utm_term=driftwood+end+table+w+glass+sets PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4427509/normal_5fec1f2ef3af5.pdfIn PDF document text
    • https://jesasifewom.weebly.com/uploads/1/3/1/4/131453969/485a3bda.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417653/normal_5f98057fd1087.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402519/normal_5fa52b06b7662.pdfIn PDF document text
    • https://cdn.sqhk.co/nupegefozub/e2jjyQT/gym_flip_mod_apk_android_1.pdfIn PDF document text
    • https://cdn.sqhk.co/matelasoguje/tgjHX4r/filling_in_holes_in_wood_cabinets.pdfIn PDF document text
    • https://kivogumit.weebly.com/uploads/1/3/1/0/131070776/lopime.pdfIn PDF document text
    • https://cdn.sqhk.co/sexifirume/gu8MNjf/antventor_point_and_click_puzzle_adventure_apk_obb.pdfIn PDF document text
    • https://luxoxika.weebly.com/uploads/1/3/4/8/134899107/2778164.pdfIn PDF document text
    • https://cdn.sqhk.co/kedilexele/mijgiBc/ruxunuwolibogajolado.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/lososimap/larry_sinclair_book_about_obama.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b2bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2BF 5304 bytes
SHA-256: 18cef1a6c43a2feb8c747572915ae0d35e17aa93717fa6fc41b0ad9aa8f07309
font_01_sfnt_off0000c4f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4F0 10044 bytes
SHA-256: d4e869575f3d53ae4f4365be0cf64b308e7bd8c93a705e98a68e004969aeca58