Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1e755c6251a8dcc…

MALICIOUS

PDF

73.4 KB Created: 2021-09-25 08:56:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 942143e7842bffbdc77c5c165386a773 SHA-1: efa619ca339b9564af380bab6c2b4b7272634f20 SHA-256: a1e755c6251a8dccbf9b639fe638c140e5ae3a7f048a2c96b89d645dcaa5f865
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and a high number of external links, many pointing to PDF files hosted on compromised websites or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The embedded JavaScript is likely responsible for initiating these redirects or exploiting vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.iciparis.ru/ckfinder/userfiles/files/vomuganugidelutexamirasi.pdf
    • https://ciiinnovationsummit.com/ci/userfiles/files/11384445420.pdf
    • http://csp.hu/editor_up/95417264651.pdf
    • http://baocaosuhoatoc.com/luutru/files/19953282511.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/161354dafbb9db---46119172183.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148b41448265---42883617275.pdf
    • http://kolbiko.com/images/uploads/file/26037154362.pdf
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/51969790947.pdf
    • http://autosvilar.com/uploads/ckfinder/files/tebometorazelitafe.pdf
    • http://domosplast.hu/files/file/2846259458.pdf
    • http://friend5190.xyz/js/ckfinder/userfiles/files/dinevubamitewojo.pdf
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/cebce9a6bbb62de4982270816d0470e5/89566847079.pdf
    • http://veterinarioassociatopacinidallatorre.eu/userfiles/files/89314373450.pdf
    • http://dulichtantai.com/files/uploaded/files/wasukojozuviso.pdf
    • http://afghansolar.com/userfiles/file/61596881819.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/16130272dee286---85482358502.pdf
    • http://seanbittinger.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lelapij.pdf
    • http://korsorlampang.net/user_img/files/xitabibipazubazupa.pdf
    • http://caydinhlang.net/userfiles/image/file/47820069890.pdf
    • https://peoplehelppeople.net/uploads/File/wavigi.pdf
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/06i6uvn9ns8c52ce6kaq9jm98c/70827133658.pdf
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613b469ecb8f2---wegoxuxutelujijapoj.pdf
    • http://zamaro.cz/images/fcke_files/file/85223990213.pdf
    • http://opsir.eu/files/file/22201602210.pdf
    • http://mobilesamara.com/img/files/file/rigunuguxafesaga.pdf
    • http://biaikatolikus.hu/files/file/kamolepebosimobi.pdf
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/gupukikezejuworunejad.pdf
    • https://ever-progress.dacola.com/upload/files/65537467325.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=firestick+tricks+best+apps
    • 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_off0000b8c0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8C0 16792 bytes
font_01_sfnt_off0000d0d7.bin
cb0743fe9503ba6757297c33067fc4e8f1d40e992e1fec70923e6a043fe03a6e
pdf-font-stream PDF embedded font (sfnt) at offset 0xD0D7 10304 bytes
font_02_sfnt_off0000e804.bin
2c62e6b7a60845c115747226838c1df957ac0c6e524701a45224dea9a81fdb29
pdf-font-stream PDF embedded font (sfnt) at offset 0xE804 18608 bytes