Malicious PDF — malware analysis report

Static analysis result for SHA-256 ed4cbdb759348d3f…

MALICIOUS

PDF

84.8 KB Created: 2021-07-13 19:44:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2b68a4ca02d70bf230da0f3a203813b1 SHA-1: 2a2b3adfb129ae11b1feedda64fdaad0919a7400 SHA-256: ed4cbdb759348d3fa57b13e074555d65c4f5292d7b8e55e1535f99d35cbc3ce6
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, many of which host other PDF files. This behavior is indicative of a link farm designed to manipulate search engine results or distribute malicious content. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious, supporting the assessment of a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2f3e48bc6---65037434888.pdf
    • https://askisan.com/upload/ckfinder/files/68254757792.pdf
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160892f92df338---nolatepugamitikoromik.pdf
    • https://leo.tw/upload/ckeditor/files/40480598359.pdf
    • http://gitishahjahanpur.org/ckfinder/userfiles/files/zoduvetonu.pdf
    • http://rauvuonsach.net/images/uploads/files/34588368933.pdf
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/9c66fed4fe9b1df39f16b8fee3e4973d/pubureni.pdf
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/sk4f6e8qeo07ldcuirqj5j61rq/82916691920.pdf
    • http://barudan.hk/UploadFile/file/20210615203203584.pdf
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/klte902aa7gfq5p68j40t3p1l2/tugotapalif.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be3e66130af---49109362468.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/4njdqs6c60pjjtp45c8tlb7bt0/58699453544.pdf
    • http://bet-balance.com/userfiles/file/jebiriruruzak.pdf
    • https://cowichanseniors.ca/userfiles/file/90917880754.pdf
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/7qk6dl91k003g8v3kjqiprpmd8/44620692397.pdf
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/b6f43aa334c817c91f452eed22975e62/35696704384.pdf
    • http://villapellegrino.it/userfiles/files/jopufiwufitu.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c1ed3ca9f85---95325623016.pdf
    • http://lamorenj.com/userfiles/files/mofebevinuraraviwivoz.pdf
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e14b5ba08---28408945364.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/28c9cf30596c4371aef06ec0e64f2f4a/dojosox.pdf
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160868fb6bd24a---gajivezuraxoxalivanokuva.pdf
    • http://matstravel.ru/userfiles/file/23070825720.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=difference+between+polar+covalent+and+nonpolar+covalent
    • 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_off0000e64b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE64B 16792 bytes
font_01_sfnt_off0000fe62.bin
c4f9ce51b008bdbd6be3e02778104ffd1c15a60ddbce47832dd567c00b230657
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE62 10740 bytes
font_02_sfnt_off00011704.bin
763b4f83b580661bc7a2720491c3fee4d2c28946eeb1b7ce7bd7fa93b6a922d9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11704 17628 bytes