Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd8e2d20b2655b7a…

MALICIOUS

PDF

84.9 KB Created: 2021-09-08 12:49:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c5e2edaa3b3a3bafc5c4449511f78ea7 SHA-1: b07ffbd84362cf4ace841b130937e178c1b4e686 SHA-256: cd8e2d20b2655b7afabd072a9858d7e53e2d80cb9db46d5b460138787d0a4673
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farm patterns, indicating an attempt to redirect users to malicious websites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the heuristics and URLs are sufficient to infer the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://synerhu.ru/uplcv?utm_term=askeb+ruptur+uteri+pdf PDF link annotation
    • https://irepairplus.nl/app/webroot/files/userfiles/files/36604647615.pdfIn PDF document text
    • http://xz-brand.com/ckfinder/userfiles/files/wabowupel.pdfIn PDF document text
    • https://censcakmu.org/board/file/files/65959599303.pdfIn PDF document text
    • http://frchem.cn/upload/files/97573711487.pdfIn PDF document text
    • https://mmeasar.com/mmeasarfiles/file/kurafexasefipuwiveguw.pdfIn PDF document text
    • http://thebankcardservices.com/uploads/files/xegetiwabivenirunefajan.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/831120423.pdfIn PDF document text
    • http://beiks.info/public/file/19829717565.pdfIn PDF document text
    • http://salonmysliwskirys.pl/userfiles/file/xirikizigavikase.pdfIn PDF document text
    • https://ms1oke.com/contents/files/xukedirosidufuxamovuj.pdfIn PDF document text
    • https://acp-luxusingatlanok.hu/ckfinder/userfiles/files/pujinoxaleduxuw.pdfIn PDF document text
    • http://gruppocaminiti.it/userfiles/files/zidadazaso.pdfIn PDF document text
    • http://savitaco.com/uploads/images/files/notaxujobalamame.pdfIn PDF document text
    • http://chafewyuok.handysociality.com/upload/files/pozulasosivuxutefenuge.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f81e607f47---kazedirosofonaxuwune.pdfIn PDF document text
    • http://www.pzkexie.com/up_files/file/suvutez.pdfIn PDF document text
    • http://xn--b1agpbmdtf.xn--p1ai/upload/file/makagilelidedib.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/vumatevosotati.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/6184281b16c2b98db5c86a3761543bee/piwinanuvafamevexover.pdfIn PDF document text
    • http://bptramptour.pl/files/file/23487379282.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/161355a7feb744---nafax.pdfIn PDF document text
    • http://medical-1669.com/userfiles/files/99957671636.pdfIn PDF document text
    • http://geoass.eu/userfiles/files/nigetowetesapanuxunetof.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/39544745687.pdfIn PDF document text
    • http://kevinmcallisterlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/19824687689.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_off0000e720.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE720 18104 bytes
SHA-256: 28499ae0526ed94927f267ef9583c4c65b164f97517c44616d0039a856e2936e
font_01_sfnt_off00011690.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11690 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012ea7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EA7 10372 bytes
SHA-256: abf15681a4d8636201e5959979799379d9f2df229027f30e23b33c112cacfd12