Malicious PDF — malware analysis report

Static analysis result for SHA-256 a83ec1cd8aba3767…

MALICIOUS

PDF

85.8 KB Created: 2021-06-29 06:50:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a433e3647df2712b1a309aa33b2e025b SHA-1: 280fa963fe7bca9639a71c1d7dce3a273310c35f SHA-256: a83ec1cd8aba37674d952ca692ececc0f7ddfea38b8fb88d95d353818054802c
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple PDF link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://benqmusicworkshop.com/fupload/file/28742222075.pdf
    • http://sevimticaret.net/userfiles/file/15358688335.pdf
    • http://amctop.com/board_data/editor_img/file/202106171914.pdf
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/siv9hdkgi4nd3vh9jo9i0p24l2/xogubidavozugupurokiwigas.pdf
    • http://fittbike.hu/files/file/66433444978.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a511f349982---ziwaxom.pdf
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/16093aff1c95d7---25840927133.pdf
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//37113237059.pdf
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/ba3fcd65ac3e22c24257de57e9a39012/46471203217.pdf
    • https://annjulieskarpmo.com/userfiles/file/zomedonomusiwobitap.pdf
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/r9f7rf81a3mnros3nv12aptkfb/rakadetegolowemazo.pdf
    • https://boucherienabli.com/uploads/FCK_files/file/50902430327.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/7c1a19e2245d166ffe01e1b87e15f0cc/tezimuwovibowepinegeza.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b9e53932241---koxafagupopukolurexin.pdf
    • http://uralinteh.com/uploads/files/dowidagosibogoxabubo.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f64b98d502---kelakijamunezepelemug.pdf
    • https://stvorki.ru/files/file/depagimawukeweg.pdf
    • https://agatanorek.com/files/file/93389583572.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/17o0p5j4dv3e05bvokvhrs64l0/rolexino.pdf
    • http://cesiedizioni.com/userfiles/file/56385901127.pdf
    • https://pet-fashion.ro/mm/file/kasixu.pdf
    • http://mid-europe-ex.com/images/blog//file/49304787140.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=another+word+for+motive
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/be98c45ea840b56cb8f0bb01342f3c47/jerim.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_off0000ed92.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED92 16792 bytes
font_01_sfnt_off000105a4.bin
6ba004720723de4ef47d28d36454f81c312b54e00a0f88f7633fe1aebde7403b
pdf-font-stream PDF embedded font (sfnt) at offset 0x105A4 16876 bytes
font_02_sfnt_off00013139.bin
e542ce1d038cf95aae4b9536218a19a965f0fbd0bc8a363db8a95c016f18f3b7
pdf-font-stream PDF embedded font (sfnt) at offset 0x13139 10376 bytes