Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa59777b53b3a244…

MALICIOUS

PDF

77.5 KB Created: 2021-09-20 14:00:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 032e010928a94fa6f7d7fb05682f7a41 SHA-1: e1fe941c45da5bdf2694c602e63069a477137bfa SHA-256: aa59777b53b3a244faefc0e58d06c9a07726e07f5324669d384018f6413bb17e
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It functions as a link farm, directing users to numerous compromised websites and potentially malicious PDF files hosted on various domains. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings indicates a pattern of using disposable or compromised hosting for distributing malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://kibbkw.com/uploads/file/5341262288.pdf In PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613273f70c1ff---68279608622.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/87ec8a38bcc2bdbfc5194e2af70fdba3/6607760491.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/rovavugamotulidorazanoje.pdfIn PDF document text
    • http://newbusan.net/FileData/ckfinder/files/20210914_E1AEF292B3457046.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133fa514f5f6---xofimi.pdfIn PDF document text
    • https://sikahaiphong.com/images/news/files/8267117984.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144ba3fb20cc---68533490004.pdfIn PDF document text
    • http://firsttimehomebuyerstudy.com/images/file/fosojisujogen.pdfIn PDF document text
    • https://aymfly.com/aym_image/files/12611405674.pdfIn PDF document text
    • http://ajej.pretty-match.com/upload/files/21702513967.pdfIn PDF document text
    • http://gibisch.info/files/files/pakalukogejivazedanomig.pdfIn PDF document text
    • http://mingmitrcoffee.com/user_img/files/vivotovogozesuxov.pdfIn PDF document text
    • https://kuzeyilac.com/resimler/files/tixelewipefexuwuzewaxu.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/02efa609bbdbf014c503bceada2db6eb/kivuxokuxuditepono.pdfIn PDF document text
    • http://iproperty.ae/userfiles/file/18575347114.pdfIn PDF document text
    • https://sistemkabin.com/ckfinder/userfiles/files/xunemaxomebokogupaliwef.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613643151f11d---41170550778.pdfIn PDF document text
    • http://sjhrz.com/images/upload/File/81473417874.pdfIn PDF document text
    • https://seeandhearbetter.ie/img/shop/contents/gesarawerunex.pdfIn PDF document text
    • http://onfireinteriors.com/userfiles/dosolufaj.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161313509968bd---vapexisasesima.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4993df8c1---kiteseramukosupudadibik.pdfIn PDF document text
    • http://asustainable.com/global/file/49908937458.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=cops+n+robbers+hack+androidPDF link annotation
    • 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_off0000c6fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6FA 10732 bytes
SHA-256: 3f97c31c6b85cc50e86c02c73720f981a8736827a8704aaaab43f68aeacf7e42
font_01_sfnt_off0000df51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF51 18984 bytes
SHA-256: 8ba019ad29ff9f0c7e6dadb914102ca192ea0852959c022ac723d8e1d51422ff
font_02_sfnt_off00011103.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11103 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1