Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d5e4acc4902c1ec…

MALICIOUS

PDF

79.9 KB Created: 2021-09-08 19:19:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7c59ffd5d2a7e11de93d7787863cb141 SHA-1: 6c11d2814c114d44fa37652c75ad343e4b008438 SHA-256: 4d5e4acc4902c1ec66e763b85b874ceba45b0dce2bce34fad9a42c0fc7fdb81b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised websites or disposable hosting, indicative of a link farm used for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm nature suggest it's designed to lure users to malicious content.

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 https://cructi.ru/uplcv?utm_term=figury+podobne+sprawdzian+pdf+gwo
    • http://morecoredesign.com/images/imageUps/files/4666711773.pdf
    • http://nachhilfeschule.havonix.com/ckfinder/userfiles/files/mafusojadixazaribudoj.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/i05v1av5cs7vmht084udmrttk5/karobazefudusovedulewagup.pdf
    • http://akinmedikal.com/uploads/file/33617816752.pdf
    • http://worldnaturalfood.com/image/upload/File/57105753280.pdf
    • https://hiperaktivite.info/userfiles/files/lixenisigudedisufupa.pdf
    • https://vaitinhdien.com/app/webroot/upload/files/78170685842.pdf
    • https://tese.in/ckfinder/userfiles/files/89428511095.pdf
    • http://0975811252cool.linker.tw/files/tukejajuxumukutop.pdf
    • https://kaptenhoki.net/contents/files/zeguvogusanumokurupira.pdf
    • http://apart1day.ru/file/bosevoxajozazuxofejimun.pdf
    • https://www.playitdirect.ca/ckfinder/uploadfiles/files/11464078621.pdf
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/abh7pb1e1nm1u4rifsutf5sdco/wedolufubexukitekupik.pdf
    • http://e-hematologica.com/users/file/gatipekuwo.pdf
    • https://ags-car.60km.com/upload/files/kigaf.pdf
    • http://thegioioto.store/upload/files/9242595711.pdf
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/161346ad088319---xafazuwitixonewurisazuno.pdf
    • https://laser123.com/geektic/files/bidevotul.pdf
    • http://www.smwiarus.pl/ckfinder/userfiles/files/43270899507.pdf
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/44618619618.pdf
    • http://lapmaymn.samdigroup.vn/app/webroot/upload/files/52572463286.pdf
    • http://upoart.com/ckfinder/userfiles/files/36945745926.pdf
    • https://ijpdua.com/contents/files/zawirokusog.pdf
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/af1c3a4248ff08b84201006fa8b78138/81627740017.pdf
    • https://sayurhijau.com/contents/files/69259472581.pdf
    • 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_off0000d199.bin
32025ec0876f4c42cd94bf86b0c5af325e1ed3fbbacbc0e5a1c309faf21ef9f1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD199 18404 bytes
font_01_sfnt_off00010018.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10018 16792 bytes
font_02_sfnt_off0001182f.bin
ef75ec22b641fddd6052992a1e1f5275d8b500fe32231e805ffc9cb48b2278b5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1182F 11004 bytes