Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d371f2fe5d2cbe7…

MALICIOUS

PDF

68.5 KB Created: 2021-09-28 14:35:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 86ea4c5a55b16f36743e13e6ea143a51 SHA-1: 5b859d47bbfb0a9dd82210cbfac7378eb3a5c295 SHA-256: 5d371f2fe5d2cbe7ed410536d2954f11a3781bffa08603860b8dbcb13fa0d79d
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 machine learning classifier and ClamAV, indicating it is likely a phishing or trojan delivery mechanism. The embedded URLs and link farm structure suggest an attempt to redirect users to compromised or malicious websites. No scripts were extracted, but the overall structure points to a malicious link distribution attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://medvor.ru/uplcv?utm_term=live+bbl+streaming+online
    • https://ensegun2.com/ckfinder/userfiles/files/30042784416.pdf
    • https://gcr.goldcrownresort.com/magazine_files/files/rikuluwatuvulopis.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161404ab1ac349---34175621752.pdf
    • http://aotwresort.net/ckfinder/userfiles/files/2680532584.pdf
    • http://xn--3e0b556bhrbowi6undva.com/ckupload/files/10758572879.pdf
    • http://quesnelbusinessnetwork.ca/userfiles/file/rigojumufudepepozuxo.pdf
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/b4oj6me7k6b3qp3h8dvihho60a/xisexiduruxepes.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/161308f5ed7394---42685393496.pdf
    • http://lnimeina.it/userfiles/files/41385012757.pdf
    • http://www.sosonomo.com/ckfinder/userfiles/files/wuzirenijuborigafuvofuz.pdf
    • http://euromarkcreations.com/new/fck_img/file/19374043027.pdf
    • http://rungrawin-itt.com/userfiles/files/69107032736.pdf
    • http://sabaispa.net/userfiles/file/nogafevapuwumupa.pdf
    • https://aldurra.ly/images-editeur/img/file/kezovotirumus.pdf
    • http://p-jtech.com/userData/board/file/sekadanazedodipu.pdf
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/8930550368.pdf
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/1429700557.pdf
    • http://remont-etalon.ru/upload/files/57197503053.pdf
    • http://xy-interior.com/uploads/files/202109041505293359.pdf
    • https://ourguarantees.com/userfiles/file/20349132292.pdf
    • http://www.koeru.eu/failid/file/41632880436.pdf
    • https://vanphongphampmc.com/upload/files/kaxizixumif.pdf
    • https://zhongzing.com/uploads/files/202109161253393410.pdf
    • http://apsons.eu/files/file/83908814928.pdf
    • http://actlogistic.vn/upload/editor/files/48248730086.pdf
    • 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_off0000afb1.bin
ef1285bc281787a392707f6a6199d3ea2b4b9a977e85a63dbdba45a789dee9fc
pdf-font-stream PDF embedded font (sfnt) at offset 0xAFB1 10616 bytes
font_01_sfnt_off0000c7f5.bin
5384efd42caeba2069be53eaf69c55a5ba6a87beb1b25ba5b14e17156742dfdc
pdf-font-stream PDF embedded font (sfnt) at offset 0xC7F5 14508 bytes
font_02_sfnt_off0000ec37.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC37 16792 bytes