Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c621318062bf840…

MALICIOUS

PDF

82.4 KB Created: 2021-09-16 11:32:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e9a6d4424235846645240baa4fc5b232 SHA-1: ff05fac09f3b805b68a434f2a768301e705bd6ae SHA-256: 4c621318062bf8407ce0afa7e3df6ff83a1b8b874f20e74bc901c25eab75a6eb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload delivery mechanism. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • 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://garglob.ru/uplcv?utm_term=how+to+block+calls+while+playing+games
    • http://cateringkieuan.com/uploads/userfiles/file/wojinozorero.pdf
    • http://chongros.com/userData/board/file/ditizexagilasipo.pdf
    • https://glycocalyx.nl/userfiles/image/file/1021298594.pdf
    • http://www.omt.ntou.edu.tw/ckfinder/userfiles/files/ponexuvikewowobutuk.pdf
    • http://carshopm.com/js/upload/files/41608628146.pdf
    • http://csc0532.com/userfiles/file/20210909082115_vxfk5l.pdf
    • http://madmojo.com/fckupload/file/julisexi.pdf
    • http://omonetach.pl/foto/ilustracje/file/43771773739.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613820994bc92---komix.pdf
    • https://www.koreayokogawa.com/ckfinder/userfiles/files/lolutofepojadabena.pdf
    • http://ieltsadd.ir/cache/fck_files/file/nunade.pdf
    • http://zekejozsef.eu/FCKfeltoltott/file/48174724910.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136e7dab477e---mikefenibilabipaxivusur.pdf
    • https://oferta.lt/i/File/30074669341.pdf
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16140c446c3852---14203917693.pdf
    • http://amblesidewindermere.ca/fckuploads/images/file/93956183936.pdf
    • http://zangerlelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bimow.pdf
    • http://majedalkarkhi.com/pics/file/zarotidomup.pdf
    • http://youngshiny.com/userfiles/file/1631738897.pdf
    • http://almawred-sy.com/files/adminfiles/files/xubagaledamibobazixukasum.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/e6a0da96b6c324e8daf407cdb182e5a0/renotinakiponine.pdf
    • https://adsbudget.net/userfiles/file/93807925081.pdf
    • https://bc2000.order-pro.com/ckfinder/userfiles/files/dosila.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_off0000db05.bin
8a5311bed4387f9af38d144b2591a4dac7bf65d7184c5f976d4753322060b8c9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB05 18180 bytes
font_01_sfnt_off000109e1.bin
b688bb8ab44eeb7d41a225cee21962c69ca3a5fbb2d4dca7c45d7fe6e6e3c344
pdf-font-stream PDF embedded font (sfnt) at offset 0x109E1 11144 bytes
font_02_sfnt_off0001239e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1239E 16792 bytes