Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4c073bcad710a49…

MALICIOUS

PDF

72.4 KB Created: 2021-09-15 13:04:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1799523fd694290d3c7c7f8a28fc19a1 SHA-1: 842f4b45989fa5aef12cff3fefa43d9a8aa2864c SHA-256: a4c073bcad710a491a3772a0453a288d4ba88739e9ac0a31f596201ef24a03d5
156 Risk Score

Malware Insights

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

The file is identified as a malicious PDF by ML classifiers and ClamAV, indicating it's designed for phishing. It contains numerous links pointing to various domains, likely intended to redirect users to malicious websites. The presence of multiple PDF link farm heuristics suggests a deliberate effort to obscure the final destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://chcial.ru/uplcv?utm_term=world+english+3+third+edition+pdf
    • http://kamkmori.cz/ckfinder/userfiles/files/runopixitamoso.pdf
    • https://investmentskillsgroup.com/images/userfiles/file/bakigedub.pdf
    • https://nycsmindia.org/ckfinder/userfiles/files/24234502059.pdf
    • http://xn--h49al71atridzo.com/userData/board/file/tewogibevezubokon.pdf
    • http://tatugigo.com/ckfinder/userfiles/files/samaniwolagaxudujag.pdf
    • https://yaofangpeixun.com/upload/files/15519720168.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130d7e769906---89052738172.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16141b3eb89bc9---midilaruxopiragovos.pdf
    • https://rainbowfurnitures.com/files/files/13887326835.pdf
    • http://studioagronomoserragiotto.eu/userfiles/files/bamuzagosuza.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161365650db50e---89548918018.pdf
    • http://alibabashipping.com/userfiles/file/33494348437.pdf
    • http://cp-tournament.org/ckfinder/userfiles/files/18397484762.pdf
    • http://mobilenmr.com/files/files/61263762037.pdf
    • https://renetravel.ro/images/files/kavig.pdf
    • http://mxag.com/upload/browse/file/72468480291.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161410e5c01378---tiginexufewininovov.pdf
    • http://olddieselparts.com/ckfinder/userfiles/files/bimamamifubemogimigarilo.pdf
    • https://istanajpdua.com/contents/files/dawisapewa.pdf
    • http://xn--h1agcmh.com/ckfinder/userfiles/files/zazinavikevuleso.pdf
    • http://shipagents.nl/uploadfiles/file/23539436935.pdf
    • http://first-group.kr/ckupload/files/49811676962.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_off0000b5b4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB5B4 16792 bytes
font_01_sfnt_off0000cdcb.bin
6fe6ab46072c020470d91acea7cb9cda71ecfeee629278cf45bea15113d96c35
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDCB 10780 bytes
font_02_sfnt_off0000e656.bin
83690c3a1e636cfec80bafe9baf401122d83d1ff72749f925e2b0acc91b249ea
pdf-font-stream PDF embedded font (sfnt) at offset 0xE656 17648 bytes