Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a8faccb6c868f63…

MALICIOUS

PDF

79.7 KB Created: 2021-09-01 21:03:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 65fdfa284e85924bd42f67cffc8f1bb7 SHA-1: 31211cbb0da2fb3e4517b728017060e4b3d816fe SHA-256: 5a8faccb6c868f63e2c1b213605afae38c875a960e919d1c20ae9919f32db475
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised websites and disposable hosting domains, likely for phishing or malware distribution. The presence of external URIs and link farm heuristics strongly suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://coretry.ru/uplcv?utm_term=arteries+veins+and+capillaries+in+the+circulatory+system PDF link annotation
    • https://www.ndgai.com/wp-content/plugins/super-forms/uploads/php/files/2c8k377cl0tusv915mcmj7f5ua/kejedejaxopumi.pdfIn PDF document text
    • https://shibbirs.com/media/files/51744558765.pdfIn PDF document text
    • http://prttour.ca/FileData/ckfinder/files/20210708_615F8F72E3A3D119.pdfIn PDF document text
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/68683554100.pdfIn PDF document text
    • https://jasz-pap.hu/UserFiles/file/24474080563.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160e5546d6a1cc---73939540952.pdfIn PDF document text
    • https://premium-house.uz/images/file/70486448358.pdfIn PDF document text
    • https://247hvac.ca/fabulous1/uploads/files/wezemepokesopojoliwer.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16071cc31eaccb---sagafewuw.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dabd57ec42---60406707022.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/susaliz.pdfIn PDF document text
    • http://progfin.pl/userfiles/file/jikofovad.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160882779308c3---wudugikazonisusikojenadew.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/596a5b172d2487a078ae4f59ac8e05cb/30360316719.pdfIn PDF document text
    • https://upbilbao.com/ckfinder/userfiles/files/fajoxuvilirebuvijagavogo.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a18b04e2b4a---nafedetumamizoxorata.pdfIn PDF document text
    • http://chapelguild.com/images/usr/jaxevoralilefu.pdfIn PDF document text
    • https://skvely-kup.cz/files/file/xonilabu.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608bbcc2133cc---6150977668.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_off0000d324.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD324 11040 bytes
SHA-256: 1b5b4b6371ebe8a1d8d47994bd904934cb5eb5ab6ea327ebbc25f477d13eb50a
font_01_sfnt_off0000ecb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104C3 16780 bytes
SHA-256: 1cc52d8231cc7903e772db0ab3923ab2f691494c2495c154a4afaac533a2d327