Malicious PDF — malware analysis report

Static analysis result for SHA-256 c96b6c9bb29560f1…

MALICIOUS

PDF

75.8 KB Created: 2021-09-17 17:56:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 42df062f16c821af227e52c8a0aabb47 SHA-1: 18d9a126d3ce7a1bf37e546a9458e2b323fea9c6 SHA-256: c96b6c9bb29560f1962b2e928774a3e84aaf27b418bb14cc90f885d9cbb12957
156 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to compromised WordPress sites or other disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the primary attack vector is the embedded link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://archism.ru/uplcv?utm_term=to+what+extent+has+the+internet+made+life+more+convenient PDF link annotation
    • https://balarampurblock.in/ckfinder/userfiles/files/42259413479.pdfIn PDF document text
    • https://impactmediaresources.com/userfiles/file/72655133259.pdfIn PDF document text
    • http://xinyuemu.net/assets/202109/files/20210907120559892666.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/164358e1279d69ae7a6cd7c4a0ff54ff/62785343923.pdfIn PDF document text
    • https://bdaudit.ro/userfiles/file/5139977051.pdfIn PDF document text
    • http://dolonchem.com/upload/files/92190572973.pdfIn PDF document text
    • http://osayit.com/images/file/53162778675.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/bdac4580639eb76c3ff8f52bada7dd98/rumopababifoxekirawosuzoj.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613394604d950---vosubizozupotalarigor.pdfIn PDF document text
    • http://sevvalturizm.com/rsm/files/pajolamobuxubi.pdfIn PDF document text
    • https://apotekatia.ba/fajlovi/zusarunijo.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/c9878a3d9666154ef6289ad692830d18/47430340727.pdfIn PDF document text
    • http://alphamarino.kz/images/news/file/55100277237.pdfIn PDF document text
    • http://vnndt.com/Images_upload/files/37219679014.pdfIn PDF document text
    • http://didongsinhvien.com/upload/files/vejojevujenobasu.pdfIn PDF document text
    • http://hoachathoanggia.com/userfiles/file/susuv.pdfIn PDF document text
    • https://paidionresearch.com/userfiles/files/josuzap.pdfIn PDF document text
    • http://ctkupavna.ru/upload/file/79759093317.pdfIn PDF document text
    • http://bradhelferlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/9816749115.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/52215933574.pdfIn PDF document text
    • http://naturpix.ch/cmsimages/file/97990666687.pdfIn PDF document text
    • https://accu-split.com/userfiles/files/2780267956.pdfIn PDF document text
    • http://www.lalorraineperdue.com/documents/56246251563.pdfIn PDF document text
    • http://vasset.bg/userfiles/file/44869732752.pdfIn PDF document text
    • http://charivne.info/images/file/lapinem.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210904023531718.pdfIn PDF document text
    • http://buyyoutubecomments.com/ci/userfiles/files/82902390387.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c2d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2D6 10960 bytes
SHA-256: 6e53f3425f35649bea398abc8eb09410e0f2c678cc2f94c657f725ac9af6128e
font_01_sfnt_off0000dc2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2D 17540 bytes
SHA-256: a9797fdaaa1aa9c1dbaadf29c6cf6f255825376c224a85ae5bec94df102f16be
font_02_sfnt_off00010907.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10907 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1