Malicious PDF — malware analysis report

Static analysis result for SHA-256 a91bcb205b07b688…

MALICIOUS

PDF

79.2 KB Created: 2021-06-13 11:01:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: e51678ba0c9a4f27f3c69935aff3eaa8 SHA-1: 9cacdee9086b059df2d96f214f19104d60febbb8 SHA-256: a91bcb205b07b6888a6ea4575ab12d90b16eae0716c9a0681d5ca563afdf22d9
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many hosted on compromised WordPress sites, designed to act as a link farm. The document body, though heavily obfuscated, suggests a lure related to 'Manga one punch man chapter 135', likely to entice users to click the embedded malicious links. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://krisoc.ru/uplcv?utm_term=manga+one+punch+man+chapter+135 PDF link annotation
    • http://www.anclupnapoli.it/userfiles/file/1603514659.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/rididozufoxuvuzaweke.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abd1f0ba171---29584831377.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a16d04cc4---91597006408.pdfIn PDF document text
    • http://tjsijiqing.com/ckfinder/userfiles/files/2021/0603/df3583111c81381443df886d1d92d921.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160926005b92ab---51095486256.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ba01805ab8b---32942986285.pdfIn PDF document text
    • https://monuments-msk.ru/wp-content/plugins/super-forms/uploads/php/files/1b3640e0da1da777d829e7686c4ef5c0/nuvakevafoxujawujodagana.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/160af7bc8082c1---sojemomuravabem.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/8b1c6a1da3459e64e456081098d011bf/ritokozunizaku.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc96b53d06---reworinajaralab.pdfIn PDF document text
    • http://bigsvatcharasith.com/userfiles/file/40630650121.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/0e4163e04fa74d7380729fa8d834b440/77884867495.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
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC45 5316 bytes
SHA-256: 86d1eed2b2bddd88aa2f41347c74871d15be131efccfdd52fa5ef72209225598
font_01_sfnt_off0000fe32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE32 10988 bytes
SHA-256: 4ccafb9484f7cc09ba1050c551e8225cb94ce164d331634707b8807562ac9258
font_02_sfnt_off00012239.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12239 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34