Malicious PDF — malware analysis report

Static analysis result for SHA-256 a58d08122b6cf23d…

MALICIOUS

PDF

333.8 KB Created: 2021-07-03 14:41:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 6cd483dc45a7a5a45a18d251c6e56aec SHA-1: ac16f255e5a33a1f8e6ccfcefed57747d77ca12a SHA-256: a58d08122b6cf23dccd187efc0ed6b8967fd43d0591821dd2df589d7a75c96fe
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links pointing to compromised WordPress sites and uses an SEO redirector, indicating a phishing lure for free downloads. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9797

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
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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.
  • 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://investmentskillsgroup.com/images/userfiles/file/47976284788.pdf In PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/cb09866192de952b8c3e9879fc4fd5a8/mamijivuzikipakirim.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/eoobfn891gl29uoqo815o27uv5/rilibaxuruwineveriruli.pdfIn PDF document text
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/80b4038b8ea2224318d8a83a63377171/bewuwofusakekepirigus.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/13554268427.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607f3120dce3e---93498650733.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/fejerowipofigozeluxi.pdfIn PDF document text
    • http://puppies-4u.com/clients/e/e7/e7f09595da74c05d2059c741134300d2/File/35417299767.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609863d9d9085---2239342132.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607882150c081---90809769846.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/e2718a58690458f1b5c7ebbbff767f12/verigutisazafixox.pdfIn PDF document text
    • https://instalacje-elektryczne.net/ckfinder/userfiles/files/kekubebadivenatatun.pdfIn PDF document text
    • https://decoveinvestment.com/userfiles/file/kuveb.pdfIn PDF document text
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607b77134a80b---29408365417.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160b43a0a564c4---pugugulebifemunoratuwalon.pdfIn PDF document text
    • https://sakkestadbil.no/userfiles/file/kibudurov.pdfIn PDF document text
    • http://manavpublicschool.org/manav/userfiles/file/dixelirib.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1608b2e1e818e0---86405786307.pdfIn PDF document text
    • https://kompaspt1.com/contents//files/25739732753.pdfIn PDF document text
    • http://marcus-1.com/FileData/ckfinder/files/20210529_F8EDF08092B10895.pdfIn PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/29118177084.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/f5pcudnpf9m6r9in7e1nq32c3s/laxisusesa.pdfIn PDF document text
    • http://drukarnia-skawina.pl/app/webroot/media/files/10228591084.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=what+does+salary+grade+21+meanPDF 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_off0004c9f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4C9F5 17412 bytes
SHA-256: 9547541075d082f52e0d2124e7133573ea96733d3b9576b22808af6c0c2eb007
font_01_sfnt_off0004f7ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4F7BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00050fd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x50FD1 10884 bytes
SHA-256: 0155161afa40fd560f64ae81bc4768636c8dd2e8e7d1fba446430c646d8cdc66