Malicious PDF — malware analysis report

Static analysis result for SHA-256 193a8d11a1a6d530…

MALICIOUS

PDF

79.2 KB Created: 2021-09-15 23:28:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 290ca734fbe0c5112b09444e530175f0 SHA-1: 61532f5c1df569685c72426f409052913db44474 SHA-256: 193a8d11a1a6d5304a0939545aac1673a9fc80e67eb1efa30a368e75221df6a8
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point 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 distribution through these links. The document body is heavily obfuscated and does not provide direct textual clues, but the heuristic findings are sufficient to infer the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://nomylo.ru/uplcv?utm_term=how+to+remove+filter+from+old+snapchat+picture
    • http://innotack.com/userfiles/files/44329916021.pdf
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161363a0c577af---21537863504.pdf
    • http://swaptoys.org/ckeditor/uploads/files/nopagijoxixoxomu.pdf
    • http://thingsantiquesla.com/userfiles/files/27524296737.pdf
    • http://lngpetro.com/userfiles/file/feroxafogudejozarifawibi.pdf
    • http://tcihk.com/userfiles/lusavogokijixusekijakobu.pdf
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1612fef49af02c---dodev.pdf
    • https://talaa-obour.com/webmisr/uploadwebmisr/file/rilazuvox.pdf
    • http://aatmicscience.org/asuserfiles/file/dixebodepifi.pdf
    • http://americandeliorder.com/uploads/files/merufuxofolugisukigog.pdf
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/33763574029.pdf
    • https://100tmt.com/uploadimage/files/20210906195905.pdf
    • http://dar-tom.pl/userfiles/file/64101938280.pdf
    • http://retailcop.ca/files/45121606798.pdf
    • http://architettodrabeni.it/userfiles/files/14901727564.pdf
    • http://centralgiving.com/media/userfiles/file/fijibogadabifemalogibe.pdf
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/161404ccf8eea2---56157010391.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc1b929eed---71085265424.pdf
    • https://willmarareachamber.com/ckfinder/userfiles/files/11028425580.pdf
    • http://minuspk.ru/minuspk.ru/userfiles/file/59530271974.pdf
    • http://donghotam.com/luutru/files/49643838274.pdf
    • http://sunmoon-glory.com/web/upload/files/39009265634.pdf
    • http://gamax-motor.cz/data/dokumenty/xagos.pdf
    • http://yuilchem.com/userData/board/file/kigikigaj.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_off0000cfb4.bin
3a40dc9e90629e67e7be2e586f7a78664fbf5f5cc56af4881d50b3390e9485e6
pdf-font-stream PDF embedded font (sfnt) at offset 0xCFB4 11128 bytes
font_01_sfnt_off0000e982.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE982 16792 bytes
font_02_sfnt_off00010194.bin
5ccc81d4749abf2351bd2726afa111b0539c37ee9ee5944342c42b5d9817b28f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10194 17756 bytes