Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c5aed11ca6d4fe1…

MALICIOUS

PDF

70.8 KB Created: 2021-10-04 06:00:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: f85f557edd4e4a8ca313f48dbf17b67d SHA-1: 38efb0afdc2475454aa0228802f38beb9839977d SHA-256: 8c5aed11ca6d4fe18be3154e1a7acdab5b5e8f4e228249ce983cce1ca8753331
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating it is likely a phishing or malware distribution lure. It functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting. The presence of multiple external URIs and link farm heuristics strongly suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://iwanbim.iwan.co/userfiles/files/zelefidemumumujupowidi.pdf In PDF document text
    • http://huabulaw.com/uploadpic/2021-9/file/2021091912011573499.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/17278286767.pdfIn PDF document text
    • http://thsport.dk/userfiles/file/42245236816.pdfIn PDF document text
    • http://ambcavallon.eu/userfiles/files/8997395639.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/5fc22b183ccc0895dd3fdff10cac6fea/6370487228.pdfIn PDF document text
    • https://wupaojichangjia.com/d/files/zizosevojek.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1aceed0ed---86920081034.pdfIn PDF document text
    • http://boracayg.com/FileData/ckfinder/files/20210910_97305DB038CEA021.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/99fbce45fb2696041ebd85a7d7a63c21/99096866508.pdfIn PDF document text
    • http://abwingsjanaf.com/uploads/files/tazanap.pdfIn PDF document text
    • http://seatraveltx.com/uploads/files/sokimasawisamozezu.pdfIn PDF document text
    • http://gibisch.org/files/files/64625443927.pdfIn PDF document text
    • http://simp-q.ru/userfiles/file/37465435022.pdfIn PDF document text
    • http://gr-chem.com/upload/files/mebaleduvore.pdfIn PDF document text
    • http://studiotecnicolamanna.com/userfiles/files/xenumerireta.pdfIn PDF document text
    • https://jeevadhara.org/work/london/userfiles/file/38091066304.pdfIn PDF document text
    • http://pappteam.hu/userfiles/file/zululiwumadoponu.pdfIn PDF document text
    • https://repairbase.net/FCKeditor/editor/filemanager/connectors/php/images/file/99126559979.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150b5d91ab41---74295064139.pdfIn PDF document text
    • http://ladyvenus.it/userfiles/files/kukuzejabo.pdfIn PDF document text
    • https://almavilag.hu/files/files/70463315746.pdfIn PDF document text
    • http://teplorium.su/userfiles/file/76026512879.pdfIn PDF document text
    • https://zbmbudomont.pl/userfiles/file/wiriwunopezu.pdfIn PDF document text
    • https://safewatersolutions.in/ckfinder/userfiles/files/degezebedizomurejakuk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=red+blood+cells+functionPDF 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_off0000b1f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1F9 10492 bytes
SHA-256: b4e4a3e150cb5e38e1612fcac5c483e1c5883c2219a833b94626f3ddf100df9a
font_01_sfnt_off0000c9eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9EB 17332 bytes
SHA-256: c7e8b8f421defd311f08ab1475d6c626cac9312a85a66b15150fb92752cafed1
font_02_sfnt_off0000f5e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1