Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae9eb6f02ee327d4…

MALICIOUS

PDF

129.4 KB Created: 2021-06-24 22:02:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 6bc17ea283ae836bcfcd53574951d46e SHA-1: c5ccca692f39188620a28d1b839d2fa5c8c0935e SHA-256: ae9eb6f02ee327d4fda600151ae8a5e363119ed6b4cd30ca377d7ba8b4ecb295
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The document body's metadata suggests it was generated by wkhtmltopdf, a tool often used to create PDFs from web content, further supporting the link farm hypothesis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 http://hakkabrothers.com/userfiles/file/%5C/sagobafirajado.pdf In PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/vsqhrn6frlgesh45p5pktvaft4/nolupukimolotevebiwabu.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607bbfe5906a3---94548310238.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa9f4fe0184---virozir.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/f062810df37a6400383708ac35eb1fa2/rorojasimifakowixiwawof.pdfIn PDF document text
    • http://ekachaiguitarist.com/ckfinder/userfiles/files/19417507533.pdfIn PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160715b7249a16---musugi.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/rlqumi10qq5h748b8vn1etq8f7/gozogaxodaxeguro.pdfIn PDF document text
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/0c8f978db7d7b5f0f533f05aa491f4c5/15540069884.pdfIn PDF document text
    • http://thanuyentea.com/ckfinder/userfiles/files/9653368283.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/l9a5l66enimhcuasvdf04gee90/53475191375.pdfIn PDF document text
    • https://vannordenvastgoed.nl/userfiles/file/zanuzapoduloparivufedenak.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=top+notch+3+answerPDF 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001937c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1937C 4932 bytes
SHA-256: 655f4045492ef949138ab3f45d53a36a6db77256d8463e503d8854acc70af548
font_01_sfnt_off0001a438.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A438 17708 bytes
SHA-256: 814a3a183bdb84f5c388ddad3ca2b6d433a3093f3e171ff42d76508252a6c74c
font_02_sfnt_off0001d310.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D310 16192 bytes
SHA-256: 8722eff906d337ac702ef5001daff75ffbfc063bda5936d936b89d730b6e1476
font_03_sfnt_off0001e852.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1E852 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c