Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c112c6d806cd7a5…

MALICIOUS

PDF

87.0 KB Created: 2021-06-25 14:06:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8547750434976c6a9a97601a87be328d SHA-1: 4bbc8da314d7e773b8a06fe7b9378e01541971c0 SHA-256: 1c112c6d806cd7a56ad6787b73053a41e127aba8cd89fdad54b5a85a81fcbac2
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple URLs, many of which are hosted on compromised WordPress installations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic confirms the nature of the links as a link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160722fd633f78---tonilekise.pdf
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4b583d1a19---nipanopajasajez.pdf
    • http://raffaelecavazzoni.com/userfiles/files/zogumiwuxelapola.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e3a7de4a40---61821177231.pdf
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c0a1427c6ac---zosof.pdf
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/9be45c602570ec828b0dfaa4ad6279d6/pomagolakudivekazon.pdf
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/c270ab8c324b1fe580b875bbe96a3897/kuzodizedobuwuke.pdf
    • http://buddhavehicle.com/userfiles/file/94143121255.pdf
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160941ef066a33---97978454143.pdf
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/2a1a89b999e41542643bfd3302522eb3/61441623195.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f109eb5a3---85778251421.pdf
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/cnpjur047ucugl1gra39t1s9si/75024427363.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160877b5ea2f1c---89458938494.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160c89668d90d4---zidumoxivevalebutoxatamov.pdf
    • http://barudan.hk/UploadFile/file/20210620150214804.pdf
    • http://geyikkimya.com/userfiles/upload/file/wotogejiwatijapaxatuja.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/6bhdb4u413l47r6proomf2r8ei/waxisogo.pdf
    • https://cowichanseniors.ca/userfiles/file/72184126697.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=asterisk+the+definitive+guide+5th+edition+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_off0000e6ef.bin
ad16cbc3ad087837d2d1533a1cdb36a44befcb2687bb2e11b19dae0a141c28f7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6EF 21692 bytes
font_01_sfnt_off00011d72.bin
d7ca1aa5593677c74aedaa60dece8c68cc204a2684a2093b3af7b6ef63404510
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D72 10940 bytes
font_02_sfnt_off000136a6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x136A6 16792 bytes