Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa399e3d0c0084e7…

MALICIOUS

PDF

70.4 KB Created: 2021-10-03 09:33:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 97b7484a84d0c72dd96c7d98572de4f8 SHA-1: e7f3343ad37d38c266e008534ec3469c9aa2f1e5 SHA-256: aa399e3d0c0084e7313a9d1b01623a2ed17a19258a51cff1e6cb7a98b56d3ab2
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to lead users to malicious content. ClamAV and an ML classifier both flagged this file as malicious, specifically as a phishing trojan. The presence of multiple PDF link farm heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://prospekt-rostov.ru/ckfinder/userfiles/files/81678127357.pdf In PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143f6095141f---48067888615.pdfIn PDF document text
    • http://drivescuolaguida.it/userfiles/files/jebupez.pdfIn PDF document text
    • http://werder-ritter.de/UserFiles/File/19138636875.pdfIn PDF document text
    • http://goldenmallbiotech.com/upload/files/vuvamapizerujuroge.pdfIn PDF document text
    • http://bjbtrh.com/files/pic/file/sifevunigaxex.pdfIn PDF document text
    • http://thegioichuyendong.info/app/webroot/upload/files/towakuzej.pdfIn PDF document text
    • https://ezsprinting.com/userfiles/file/wadudininezobebes.pdfIn PDF document text
    • http://gyogytornasziget.hu/uploads/files/63846496790.pdfIn PDF document text
    • https://ms02bet.net/contents/files/10119397725.pdfIn PDF document text
    • http://platypusspot.org/uploads/ckfinder/userfiles/files/98710742210.pdfIn PDF document text
    • http://gyn-ordi.at/myPix/file/48366889174.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/16155befa854cb---92700198319.pdfIn PDF document text
    • https://medbillings.us/lightspeedweb1/file/33815356734.pdfIn PDF document text
    • https://mmrh.myagenda.cz/pictures/editor/files/zisosegul.pdfIn PDF document text
    • https://pharmawell.eu/ckfinder/userfiles/files/3541577048.pdfIn PDF document text
    • https://mondoaudio.it/img/uploaded/file/7603824962.pdfIn PDF document text
    • http://proart.by/media/file/kijasubelaselakemu.pdfIn PDF document text
    • http://bargiel.com.pl/ckfinder/userfiles/files/jefim.pdfIn PDF document text
    • http://svb-volleyball.de/userfiles/file/godivixaniwe.pdfIn PDF document text
    • https://myshalewell.com/userfiles/file/74281184097.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16131f9d52c095---modufasimarurodirudinima.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/46189890390.pdfIn PDF document text
    • http://ambiance-cinema.fr/wp-content/plugins/super-forms/uploads/php/files/e31c21efb455ac0e35153ccf43c92a8e/4054452837.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=spicy+chicken+adoboPDF 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_off0000b2ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000caff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAFF 16468 bytes
SHA-256: ffdc0c0ba07dc45d766b9d4de0307cd574fb10174fc2c7bf1fcc2a8ae688ea79
font_02_sfnt_off0000f403.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF403 10620 bytes
SHA-256: 79d56b15a7e55289f17860eb11dfc964f96526275d5f84e9e300f8a20950bc88