Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e83d97a9c9271be…

MALICIOUS

PDF

99.9 KB Created: 2021-06-23 09:46:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 92cee190b8d35d39b06776239aebc5eb SHA-1: 21439f0f52ac5858d782a4b07566e4eeb64a4194 SHA-256: 3e83d97a9c9271be5c46d211adc98fd5a8cc3963474e69fe8b90ab3bc1f02a24
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress sites, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/3qogqjg69usme6op525gub0tte/89210227605.pdf In PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160750c9862b83---36538930851.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606c6b49dbf07---58693545969.pdfIn PDF document text
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/349fdbc825191d789c301191ecc4746b/4245579771.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078bd8c09fb3---43784140836.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a2bf05b68f5---30609422043.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/b373d12dabc27db29eef13bfd9a3b1ff/liwuzunol.pdfIn PDF document text
    • http://bigxra.com/uploadfile/file/2021051302230073499.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/guvotuvituz.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0c5ac93350---dumoruzujiwuren.pdfIn PDF document text
    • https://bistakalikotenetwork.com/userfiles/file/69974260935.pdfIn PDF document text
    • http://geoodwierty.pl/files/file/bavigenarelob.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/butegasoji.pdfIn PDF document text
    • http://shreejians.com/userfiles/file/81518857758.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/4750479018.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=arabic+opposite+words+pdfPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off00014719.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x14719 33788 bytes
SHA-256: cbeec30c24d0ee1f4728e382ba32482e85228689500fba11766cd6cc645f321c
font_00_sfnt_off000104e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104E1 5336 bytes
SHA-256: 0dfc61c6b3a52250026bcc69a14b3aece093e94da0f5555034f949392b262c75
font_01_sfnt_off00011719.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11719 1800 bytes
SHA-256: a36eee06fef6ce219692c4ec918276ac99413e4fd1e3666e4031624f9289d620
font_02_sfnt_off00011fa6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FA6 12140 bytes
SHA-256: 874c483ad246939fa58efaad53b43095ee935071cf893d68b6248e8ef92bef4a