Malicious PDF — malware analysis report

Static analysis result for SHA-256 15a9f092be1097d0…

MALICIOUS

PDF

77.6 KB Created: 2021-09-01 23:22:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e99793093aca035af2592eae0a30c005 SHA-1: f5aee15dece4750856504fd6fdbf68cc6da45f64 SHA-256: 15a9f092be1097d083c48732c47c9543d36a318cfa77abb4058fb0213f53bdeb
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing given the link farm nature. No scripts were extracted, but the structure and URL analysis are sufficient to infer a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://huntic.ru/uplcv?utm_term=how+to+pronounce+high
    • https://termocasasrl.com/file/38605889825.pdf
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/h3k1743dsnvkfmtqnb7sflcecl/14091998095.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088eb12cb4d7---murijolexadowonagoginemim.pdf
    • https://tonmathunglan.vn/upload/files/56843812321.pdf
    • http://naoshima-tours.com/images/blog/file/laresafesudipikefu.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc4baa26da---zejebo.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160872fa6da0a5---vugajisoxi.pdf
    • https://tsafar.ir/basefile/tsafarir/files/32185859431.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/8cqs5648m39a709l8425d2tqq6/lejufubapomirewiva.pdf
    • http://eprdel.cz/userfiles/file/91362107014.pdf
    • https://burragebrothers.com/demo/jolie/beta/userfiles/files/peredijala.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/160919665c138c---33834720939.pdf
    • https://psychotherapie-coeppicus.ch/userfiles/files/zixomenanosuges.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c1ca1fb8056---57926094321.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f30676ff3---91313325179.pdf
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/533304de9a0a928f8d98e963ab033e39/nikojajaxom.pdf
    • https://b2b-intelligence.it/uploads/file/vegijawotapifix.pdf
    • https://caribemed.com/userfiles/file/28663207367.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f74d09285e---77871232810.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/0mvrl5ackg2rvl8nu7m8otb2u0/64121017072.pdf
    • http://bukharageorgia.com/sites/default/files/file/xoralijoxafobemej.pdf
    • https://mytopics.it/uploads/file/weroxijovuwirizuzanaf.pdf
    • http://futuralagoparking.eu/userfiles/files/nijurumegif.pdf
    • 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_off0000cb93.bin
1910f92901b84f9dd7f568693fc70308947635673fd2ab5143d79fe4f4d23639
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB93 10452 bytes
font_01_sfnt_off0000e33d.bin
bc54b6b413d0bf10d333883a3368dded6e59131601f78a9aad35ad172e0e6384
pdf-font-stream PDF embedded font (sfnt) at offset 0xE33D 17284 bytes
font_02_sfnt_off00010fa4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA4 16792 bytes