Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4dda2643bac0fd6…

MALICIOUS

PDF

84.3 KB Created: 2021-06-25 17:37:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 354d9921f907ca9228a32811cb9c32c7 SHA-1: 879557e5ff7a27dd4340b1d644c7403a22120ee9 SHA-256: a4dda2643bac0fd696135bad5bb60a945226f8879c396c300b50df9f8f2b0911
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to external sites via the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://atut-biuro.com/uploaded/file/lajowivavifugov.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/8c06e23115efc366b06950295b747fc0/27478166347.pdf
    • https://remoteworkerclub.com/wp-content/plugins/super-forms/uploads/php/files/189d5aefad4ff1d12fd5931dca3ec2c6/fofuk.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/9gsor0jpvkientbq7g347tk436/1155413686.pdf
    • https://bednidhitraders.com/userfiles/file/48949360515.pdf
    • https://praward.tw/wp-content/plugins/super-forms/uploads/php/files/eec150ab4a812f598de51f87743e1cfb/65332718904.pdf
    • http://nature-revive.org/files/file/6228796270.pdf
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/ef3c1cabd87cb592f2a1dcf04c1f8840/67647529938.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c38bef1dddd---wuvobewedamane.pdf
    • http://chickenwild.com/upload/contents/images/images/96259908376.pdf
    • http://musorcentrum.hu/files/article/file/saxunukotezo.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16082411c64d9b---4885305707.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba8601735e4---89100882445.pdf
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/d3c1fc987d1ba8c977c13a3d688b24c0/bunokog.pdf
    • https://actorconseil.com/files/file/67974402872.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/eee138ad116c14b3c1455bd24dd9724b/tatiladaneritizuwomi.pdf
    • http://erdivigado.hu/userkepek/file/sezafetusitatap.pdf
    • http://micronforgacsolo.hu/UserFiles/file/69703174602.pdf
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16085f7ae5b8da---wafomipiziv.pdf
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/7061fbab5043999ce7fc193d32d92bf4/varovironir.pdf
    • http://teerosy.com/ipp/images/uploads/files/danovavetakeridivo.pdf
    • http://araonline.hu/uploads/file/xewajisife.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/38b2cb72a9333d58bb3e5bc8664f8331/52140384751.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=a+little+birdie+told+me+meaning
    • 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_off0000e3bf.bin
33d8fa775bfb04af41d0ccc9c5c67f60183359105a934782d80bb8045bc2d334
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3BF 18712 bytes
font_01_sfnt_off00011438.bin
4f8ed17bc8a6fbf7de3c74deacff4091ca82195e42539f9d3d3f25e55eae09b7
pdf-font-stream PDF embedded font (sfnt) at offset 0x11438 10544 bytes
font_02_sfnt_off00012bf7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12BF7 16792 bytes