Malicious PDF — malware analysis report

Static analysis result for SHA-256 28089fa0b910ae84…

MALICIOUS

PDF

70.7 KB Created: 2021-09-29 12:50:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1397b9f28b210f2ce74a6f3ab5ff5864 SHA-1: a8615c9430941df50548ece161ded94274f00756 SHA-256: 28089fa0b910ae84fab8ec7d6d89528a4ee74c095c21a07a47dd1141534d620e
176 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. The document body is heavily obfuscated, preventing analysis of specific user-facing lures, but the presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://accesoriosalmayor.com/images/userfiles/file/nitulajuxebutuwarafo.pdf
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/149ca57d54cdfe7d2ae00b2695714172/1515237878.pdf
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/19ed7a8182eef2346ebd5868604f3c52/37219271310.pdf
    • http://www.springperfect.com/upload/finder/files/vegipokajaruj.pdf
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16132c5b33492f---8349173405.pdf
    • http://fiumevivo.it/userfiles/files/gugifijer.pdf
    • http://coverybox.box8websites.com/ckfinder/userfiles/files/98524351888.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16139227ea1252---tasedopiraveragejer.pdf
    • http://tokyoto.pl/UserFiles/file/bajezukofimoja.pdf
    • http://quaisetoiles.fr/img_pages/file/12277830786.pdf
    • http://volkshilfe-ktn.at/images/content/files/90727753144.pdf
    • http://www.ferm-matic.fr/upload/file/38725748268.pdf
    • http://daisytalavera.com/userfiles/files/76958822880.pdf
    • http://www.bash.cl/media/file/luragokaluroforazopezone.pdf
    • http://serdceprirody.ru/userfiles/file/meraterivep.pdf
    • http://elskup.pl/images/assets/file/dujiluxolowup.pdf
    • http://dietetyka-24.pl/images/files/68059245677.pdf
    • http://icltindia.in/userfiles/file/34458103956.pdf
    • http://architettosbaffo.com/userfiles/files/fokazokisejo.pdf
    • http://turksebruiloften.nl/userfiles/file/polabumujuta.pdf
    • http://gasasosong.com/upload/fckeditor/file/24368649042.pdf
    • http://thenikharvconsultancy.com/userfiles/file/56399219615.pdf
    • http://yuhongzg.com/d/files/matunutiku.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=most+important+phrasal+verbs+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_off0000b251.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB251 16792 bytes
font_01_sfnt_off0000ca68.bin
3954d69b5844e1f32a51a80c42c0150ffdc6cf79e8fbd6e272af9baeac10242f
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA68 10960 bytes
font_02_sfnt_off0000e360.bin
d37c2b9a3089aa0e50fd02c3f8b4aa21646c87d2bac5725cf8e9863c7c624e55
pdf-font-stream PDF embedded font (sfnt) at offset 0xE360 16492 bytes