Malicious PDF — malware analysis report

Static analysis result for SHA-256 df4bb0193e898d73…

MALICIOUS

PDF

72.3 KB Created: 2021-09-29 01:29:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 0a6e3dcfc12f564b5e7a26bfb7d0a967 SHA-1: d66a0a6ea1f43cd684d6e8401cd49d5f326104e0 SHA-256: df4bb0193e898d738df6bafcfa18ffff318f4bdc0ae4c522d1ab77d8dceea7d8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified embedded JavaScript and a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to lure users to external sites. The presence of JavaScript indicates potential for further exploitation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • 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 https://queure.ru/uplcv?utm_term=infinite+design+android PDF link annotation
    • https://codefon.hu/js/ckfinder/userfiles/files/18431879250.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/10083907154.pdfIn PDF document text
    • http://allier.proximeo.com/ckfinder/userfiles/files/tigudifolatupilinowamuvov.pdfIn PDF document text
    • http://tnslib.su/userfiles/files/jefemipiwuzadex.pdfIn PDF document text
    • https://www.domaine-boussard-chablis.fr/ckfinder/userfiles/files/62218250922.pdfIn PDF document text
    • http://scherzerpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/37224947711.pdfIn PDF document text
    • http://microsolder.hu/userfiles/files/wijetawagonavupel.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140dafe1214b---pokonaxusixulolugepawoki.pdfIn PDF document text
    • http://vanillasky-ch.com/images/files/53168394209.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/zafusuzemadoba.pdfIn PDF document text
    • http://bangkokmagnetwire.com/ecodev_test/image_system/files/riloruweb.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/1314c0521513395f1cb26e37d5fe23d3/52476811686.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/16152737bbc8fa---tofifube.pdfIn PDF document text
    • http://kdekdyjak.cz/data/353416049.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/93419297168.pdfIn PDF document text
    • http://bulmarconsult.com/files/xopugusagi.pdfIn PDF document text
    • http://pscworld.eu/ckfinder/userfiles/files/75193226138.pdfIn PDF document text
    • https://hkpefa.org/editor_upload/file/78336389514.pdfIn PDF document text
    • http://www.sczct.com/up_files/file/10545292639.pdfIn PDF document text
    • http://aunay-sous-auneau.fr/ckfinder/userfiles/files/69465452389.pdfIn PDF document text
    • http://boschvietnam.vn/files/usersfiles/files/pulaxexomaf.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/2d2f202bfbd108a1c3eb38b8d1a316d8/36431791258.pdfIn PDF document text
    • https://opsclown.it/ckfinder/userfiles/files/92941498358.pdfIn PDF document text
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/43596400370.pdfIn PDF document text
    • 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_off0000b77b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB77B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cf8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF8D 17288 bytes
SHA-256: a75261507e9c9e51992b76bdce8ae93e18002d0f83882542edc67fdfdf496e73
font_02_sfnt_off0000fc22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC22 10436 bytes
SHA-256: 0096ab13066c5e60d8fe529cb582f3004768a044d483f16c72cc0f3b0394b382