Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1e4c51b3402c320…

MALICIOUS

PDF

87.6 KB Created: 2021-06-30 11:09:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cb677b40ae5fe1bdefea354b174dc2c9 SHA-1: 66c007d9eb5d068f3d25009f6e7a836dbac76349 SHA-256: b1e4c51b3402c3203bea15b34cc46074d0ec69173c79dcacba23d510d2263039
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other domains, likely intended to lure users to phishing pages or download further malware. The presence of multiple external URIs and link farm heuristics strongly suggests a malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9765

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://crewmak.ru/uplcv?utm_term=space+gangster+2+mod+apk+unlimited+money
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/8c38d51405705c51f2f9db50759b0fc5/28879591984.pdf
    • https://santchavarabed.in/ckfinder/userfiles/files/28646126489.pdf
    • https://hashtag.school/userfiles/file/4465348897.pdf
    • https://aduanaldelvalle.com/userfiles/file/digonulelizeni.pdf
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607d57b2e5473---87650600969.pdf
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a37053dbf19---vogix.pdf
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/9as6449keuaji13l6htl0prnjs/towaxuzuk.pdf
    • http://sunnysidehigh65.com/clients/d/d0/d00d1ad1640c45b888f5e58ac216a5d1/File/rusom.pdf
    • http://ilovegabal.net/fckeditor/_upload/file/19176823168.pdf
    • https://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/2620feccfb79c9f681ccdbf2cd561aa9/33698571640.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab25031201---jawoverejalitigewupajedug.pdf
    • https://rosenstein.lu/userfiles/files/80569906069.pdf
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/54703885137.pdf
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/e98ecedb9a60486fad66f86b66f45cc5/neviburanubexubexobo.pdf
    • https://agenciaboom.com/wp-content/plugins/super-forms/uploads/php/files/pr6rf12bubknngfsaefj783be1/11276086441.pdf
    • http://studiogaleazzo.eu/userfiles/files/pawatuwowaxusemiruza.pdf
    • http://naasschoolofmotoring.com/fckeditor/userfiles/file/27269749818.pdf
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/85114196635.pdf
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a78fe94e603---xusora.pdf
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/ukr5mj4nu74jh0b6lk858ffi8l/bedusepotavigezosawodu.pdf
    • http://cjatkinson.com/userimages/palenixepibibuki.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092fd5fc224a---kolakeliwediked.pdf
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/vt8phbqks3ql6l07hlv2cgo2v2/7887940605.pdf
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/838a5ecd34451fbfb36ee8ee01c688f5/lowelegitasenozevara.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/d4be32641a1dd2b8f2f33fe308872e01/77886110321.pdf
    • https://solo-enoant.com/content/files/files/35197744383.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dedd.bin
c2ba98ae8ca16e51c9a037dca7f01d58082c64f59f4dc40227112e7de6774b00
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEDD 11356 bytes
font_01_sfnt_off0000f972.bin
ea4c519511acc2868665930a40eb8ac3674e3e30a505700ebbefbac14f7806b1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF972 22120 bytes
font_02_sfnt_off00013001.bin
18d4e792ecce3f905fa2ab451ccfd49c5848bf831e68a40b7d1f99915d932e98
pdf-font-stream PDF embedded font (sfnt) at offset 0x13001 1696 bytes
font_03_sfnt_off00013818.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13818 16792 bytes