Malicious PDF — malware analysis report

Static analysis result for SHA-256 4da32fecb502939c…

MALICIOUS

PDF

95.0 KB Created: 2021-08-04 11:47:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2dae17ccac8693dfef0faf8a7456a248 SHA-1: 88d3e9f1a127c723e736245b3943303a75b970b3 SHA-256: 4da32fecb502939c0589ba92d068ab0444ed755a07f27bc7de35a47804890eab
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable domains, indicating a link farm or phishing attempt. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this behavior, suggesting the document's primary purpose is to manipulate search engine rankings or direct users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://guojingmall.com/userfiles/file///56155902294.pdf In PDF document text
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/aa9183679493b22b9534d6e218b075df/konud.pdfIn PDF document text
    • https://autotrans911.com/thread/admin/uploads/file/vexunovumefe.pdfIn PDF document text
    • http://oasis-inwaste.asia/files/file/potisezoxiner.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a77a3590154---jatifapup.pdfIn PDF document text
    • https://tigercabinetry.com/wp-content/plugins/super-forms/uploads/php/files/347ea6d203eb1ac70578aec0bd751e56/robit.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/140853465e24a9ddf3045af2c5f0a691/35360997999.pdfIn PDF document text
    • http://www.aluvascientific.com/UserFiles/file/670303233.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/cmng19263moib4a3m47eebsh0g/19915996962.pdfIn PDF document text
    • https://faresaldabbous.com/uploads/file/73742864823.pdfIn PDF document text
    • https://dolcezzecaffe.it/file/difadafilu.pdfIn PDF document text
    • https://keyseries.us/userfiles/file/44632996909.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/uki5u8cvofm6d65v5f73fmasfq/819902159.pdfIn PDF document text
    • http://sooclose.eu/upload/File/xebefusafe.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/7f0d53f2a9195084e5e69699e5c67878/4714159282.pdfIn PDF document text
    • https://rijst.nu/userfiles/file/digupemakinop.pdfIn PDF document text
    • http://amajyuku.com/files/files/44859300101.pdfIn PDF document text
    • https://bloc-immo.com/images/benipu.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1608100760594b---vibopotitinolunadidub.pdfIn PDF document text
    • https://art-lamps-rali.eu/files/file/2964166437.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160afd1cfb1e99---5894061159.pdfIn PDF document text
    • http://finalbrand.cz/upload/file/nunelevinofi.pdfIn PDF document text
    • http://dansungsala.com/uploads/files/bopopadubovavatepoxuv.pdfIn PDF document text
    • https://tannhatviet.vn/upload/files/tarusigibexujiwopagotud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=ultrasonic+welding+horn+design+guide+pdfPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010cdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CDB 17352 bytes
SHA-256: 6f7f1cc31012c4afaa3a78d33625205df0b3b8041ac15149fff0d3f6cd60b7d6
font_01_sfnt_off00013a90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A90 11092 bytes
SHA-256: 091e46ff43d7323c7f2d640000b90609578284be659d78f01dc86972786ef6ad
font_02_sfnt_off00015439.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15439 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1