Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a4bb3838b1e030a…

MALICIOUS

PDF

70.7 KB Created: 2021-09-28 20:56:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 05d955afe9f0db8a64fbd62ddebc9ead SHA-1: 77bd556635640d55a6e1ac63de9265651037bf23 SHA-256: 5a4bb3838b1e030ab8cc22c01f476311f8446a805c6362cdf1415f497414c0bc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a common phishing or malware distribution technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://queure.ru/uplcv?utm_term=all+the+guns+in+warzone PDF link annotation
    • http://homeopathyhk.com/files/52220756007.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/4741708fd2f645aa3372793116e98ad0/91090576604.pdfIn PDF document text
    • http://www.southpointinstitutehowrah.com/admin/uploads/file/motivuxip.pdfIn PDF document text
    • https://crossfitbeeshark.ro/app/webroot/files/userfiles/files/58010492935.pdfIn PDF document text
    • https://sharjahcements.com/images/bulk_images/files/gejodegiga.pdfIn PDF document text
    • http://cableesmaltado.com/d/files/52109144798.pdfIn PDF document text
    • http://kompletucetnictvi.cz/files/file/xudesenipuweximi.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/t9ief0ucmjbuo3vvfv6rh54ea3/zilanobixorevakazop.pdfIn PDF document text
    • https://kaktutzhit.by/uploads/files/tabiloni.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614556a270156---garobogubodasifomup.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/bijuzol.pdfIn PDF document text
    • http://fine-trading-knotwork.com/uploads/media/gelupuxoxuxajobo.pdfIn PDF document text
    • http://paulabenveniste.com/UserFiles/file/jojazi.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/fofofunukipumevejopisu.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/30363570287.pdfIn PDF document text
    • https://theshamrockpublecco.it/file/87859740963.pdfIn PDF document text
    • http://worldsocialistpartyindia.org/ckfinder/userfiles/files/60699147296.pdfIn PDF document text
    • http://zimmerei-possert.at/zopepumafug.pdfIn PDF document text
    • http://sksound.com/userfiles/file/28462282320.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/firatad.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/vuligerasakoribibogefon.pdfIn PDF document text
    • http://abwcrainhwy.com/uploads/files/30247946883.pdfIn PDF document text
    • http://daindnc.com/fckeditor/userfiles/file/rojedaxesugiluj.pdfIn PDF document text
    • 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_off0000b28d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB28D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA9F 16692 bytes
SHA-256: f40b2aacb6637b41ad2c90cb08b7314fb153de4e08955b4075c8ea95e6fc07e7
font_02_sfnt_off0000f4d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D5 10612 bytes
SHA-256: 0cd2f83dbeb61d4b57e3624468647025dcb6052d7ceb6c40810f64a497a2b58a