Malicious PDF — malware analysis report

Static analysis result for SHA-256 8279c44edc9edba3…

MALICIOUS

PDF

68.4 KB Created: 2021-09-28 07:54:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c0f991a1512a7897384d881b75154e70 SHA-1: bf254fbe618634152d512ae936ca8be176a926a3 SHA-256: 8279c44edc9edba32b4beda1759d0f2bb5ad29596e41780a4148685edadf14f6
176 Risk Score

Malware Insights

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

The PDF is identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a phishing lure. It contains numerous embedded URLs pointing to potentially compromised or disposable hosting, suggesting an attempt to redirect users to malicious sites. The document structure and heuristic firings indicate it's designed to trick users into clicking links, likely for credential harvesting or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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 http://linker-apps.com/files/fireramupokifojud.pdf
    • http://trineckevzdelavani.cz/webpagebuilder/ckfinder/userfiles/files/68007933584.pdf
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/16140338552c5e---26740675337.pdf
    • http://fc-junajted.com/upload/datoteke/zimasurogirowozegajana.pdf
    • http://burattinojatek.hu/userfiles/file/67685736573.pdf
    • http://onlineticketreview.com/images/file/6416701183.pdf
    • http://duhochoangthanh.com/upload/files/nejejav.pdf
    • http://curry-box-deluxe.de/userfiles/file/vexopelerirunor.pdf
    • http://reclameindex.nl/images/uploads/25612901739.pdf
    • http://irollee.com/userfiles/file/81812819453.pdf
    • https://volnynaklad.cz/data/file/83013959425.pdf
    • http://clingac.es/d/files/50565711631.pdf
    • http://hanshintech.net/data/file/13311995327.pdf
    • http://rungruangsteel.com/public/upload/userfiles/files/83979189282.pdf
    • https://seger.cz/userfiles/file/sofovuviwalitozupenudub.pdf
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/21579441205.pdf
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161337b065ebd0---penapixotupu.pdf
    • https://highlander-inn.com/assets/userfiles/files/xewumivowekeranupedotab.pdf
    • https://viveironativodevicosa.com.br/ckfinder/userfiles/files/13085128201.pdf
    • http://harringtonandlombardi.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/94357465590.pdf
    • http://max-metal.pl/gfx/file/3617716565.pdf
    • https://oldgradeducation.com/ckfinder/userfiles/files/kojidupiso.pdf
    • https://semagro-msw.ru/pics/images/file/velusagi.pdf
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e161490146---xisuvamuw.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=cv+europass+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_off0000b22f.bin
972a39b45db76f0759f3a2e0288851e2134fb73904433b7fa3238984c9f989b0
pdf-font-stream PDF embedded font (sfnt) at offset 0xB22F 10348 bytes
font_01_sfnt_off0000c9b6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC9B6 16792 bytes
font_02_sfnt_off0000e1c8.bin
28921e0471bd7849dd17f5dc252d10b08ec9786f3395ce5b4eb3ad7ee9e7b588
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1C8 14008 bytes