Malicious PDF — malware analysis report

Static analysis result for SHA-256 f25ff274d0c4fc9f…

MALICIOUS

PDF

73.0 KB Created: 2021-10-04 20:04:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 89bb090a362d36a595004fd527f82833 SHA-1: 6584873e3930504d7c8ba3aed4b405898a68e3be SHA-256: f25ff274d0c4fc9f586f65e26be6c592e24194939517b353f426bdb92812b38b
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress sites and disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145db63a1e70---buniridowetikafuwuxari.pdf
    • https://producedepot.us/userfiles/files/jepuv.pdf
    • http://cityfate.com/files/files/boragawe.pdf
    • http://ecompletecontact.com/ckfinder/userfiles/files/15634897901.pdf
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/tavejezulemafunopudeniri.pdf
    • https://pfhotel.gr/ckfinder/userfiles/files/43420012205.pdf
    • https://autopits-directo.migrupoq.com/ckfinder/userfiles/files/dadomesirimolu.pdf
    • http://vaynhe.com/upload/files/58359782684.pdf
    • https://resicolor.com/upload/files/zenojavik.pdf
    • http://dribblebar.pl/userfiles/file/nobedanoxutinifelazepabu.pdf
    • http://chieusangducphat.com/uploads/userfiles/file/dugipuvugotarowevagaku.pdf
    • https://visualmotion.nl/uploads/file/79634069049.pdf
    • http://www.casasemio.com.br/ckfinder/userfiles/files/depikowotunutemelifi.pdf
    • http://kqcme.yiaiwang.com.cn/upload/files/mijobotune.pdf
    • http://watch62.ru/files/files/5901449759.pdf
    • http://mrpokedb.com/uploads/files/tivanutilamujomejovi.pdf
    • https://pollackmihalyiskola.hu/ckfinder/userfiles/files/82281726014.pdf
    • https://turismo-galicia.es/ckfinder/userfiles/files/10097984090.pdf
    • http://hophungvietnam.com/app/webroot/uploads/files/vavinevaj.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16142427d106fc---82846157963.pdf
    • https://dichvumayphoto.vn/webroot/img/files/ziriluvofomenosidibaxan.pdf
    • http://giadinhlaurenso.org/upload/files/72988249112.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134eb4249526---44575351158.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=7+syllable+words
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bce7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBCE7 16792 bytes
font_01_sfnt_off0000d4f9.bin
1dae239effa2294dd6ef3d47eb3a9ac809ee8d488261c9fe5042b55d009ee405
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4F9 16552 bytes
font_02_sfnt_off0000ff64.bin
724ff6240cb9e7bb537b00363d64a5a6598741c631867b97029e3d4bb6796159
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF64 10240 bytes