Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf31c7bf5e84f55a…

MALICIOUS

PDF

87.5 KB Created: 2021-06-28 00:07:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ae9afd00e7e48efaae6db0399753d63d SHA-1: 9a5d48d5cc8405b81c78de54c7303a71194d896a SHA-256: cf31c7bf5e84f55a984c21079f0ebac533e6c33d9688e705696114fefbcf253b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm designed to obscure the ultimate destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests a tactic to leverage disposable hosting for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://inwebjor.ru/uplcv?utm_term=free+forced+feminization+stories
    • http://donaldbermanmaimonidesgolf2021.com/clients/0/0d/0d43fbb8ff91cab41fa1b056c0d912a9/File/najetexabibetisapabopawul.pdf
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aac3ff4dcb3---bizelun.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/16091e89b80ebb---83082411170.pdf
    • http://idroter.org/userfiles/files/semazakekifovapisox.pdf
    • http://seventyfirstclassof69.com/clients/60772/File/86207933606.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160beb6ed3161e---zikisixudibugajodisagobi.pdf
    • https://muzeumkonstancina.pl/attachments/file/zetubopaliwukerebuv.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/e8e6ed5acf28fafcadc11d40ef308ee9/87846852122.pdf
    • http://clear-es.net/yamituki-n/uploads/files/girilefedigizese.pdf
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160ae7d55a4b76---47930929076.pdf
    • http://foto-preiss.at/upload_files/files/50010557902.pdf
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acd5ce12ef9---24688243655.pdf
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/028177512cd050174c0ef6a534fc1df2/golozaxekogifutowizedaz.pdf
    • https://candbco.com/ckfinder/userfiles/files/75716573412.pdf
    • https://dm288.rs/slicice/file/jujewilubixatofuxago.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1d7be5646---lajelilowitifutosuso.pdf
    • http://wumag.pl/userfiles/file/fagitimitaxopepimi.pdf
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/93a8506b6bdfd0e87aa3c716458e88e5/6763220042.pdf
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/91fbf4ac403baefd7e9795b54cd4e3cc/69028329240.pdf
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/feaf16acef13bfbdba039e6854cd3f6e/sazavabudaf.pdf
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160700e51ee0d6---29904270983.pdf
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2395ba71ef---58121368644.pdf
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/3763939d64d95f8fc245326ce9e77e11/80164728700.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_off0000f16e.bin
6d4c6ffddfa92ddf011ac65eac7eba211337312b82a27caca38726e206fb0fb0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF16E 17384 bytes
font_01_sfnt_off00011ea7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EA7 16792 bytes
font_02_sfnt_off000136be.bin
3304fd8155ed5e5e43a6b4d21ed349e4f166001bbcae159297c8c38c0e623f95
pdf-font-stream PDF embedded font (sfnt) at offset 0x136BE 10628 bytes