Malicious PDF — malware analysis report

Static analysis result for SHA-256 65422fb73c15f1d2…

MALICIOUS

PDF

75.1 KB Created: 2021-09-08 02:57:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e381222adde8e9cd73e0130fd0fe6432 SHA-1: 72e0373449794a9c494ae1f82a0897a170ffe7ff SHA-256: 65422fb73c15f1d2ad7ec6e5296e5bdd8ea27b1da8a81d668a83f7f630aba624
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://archism.ru/uplcv?utm_term=cell+differentiation+gcse+worksheet PDF link annotation
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/9b6f100c5e75e8db90e2263770a03e95/81370016337.pdfIn PDF document text
    • http://greatnice.club/updatefiles/file/40467256688.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/3a9a3537108f67caa8de678bc1821e9f/19608589165.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/70623760358.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/nakisade.pdfIn PDF document text
    • http://jtour.vn/userfiles/file/49602810031.pdfIn PDF document text
    • https://magnettoptan.com/upload/ckfinder/files/kojomafixemoxajem.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606c87dc2bd40---domudegok.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160911d4ee44d0---gusudalilalu.pdfIn PDF document text
    • http://www.cerel.eu/images/wyswig_images/file/71398794151.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf7a3e61876---gegufaxemutofarozinete.pdfIn PDF document text
    • http://cathugo-yachts.de/res/wysiwyg/file/55681847339.pdfIn PDF document text
    • http://eurekaelearning.com/upload/news/file/70987075397.pdfIn PDF document text
    • https://holcom-solar.com/webroot/img/files/notefugaraborise.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/20555092419.pdfIn PDF document text
    • http://szalkasszorutacskok.hu/app/webroot/files/content/files/raxelovaxejurur.pdfIn PDF document text
    • http://bomtvplus.com/data/board/file/20210515195227.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/mejalibupokusabozekutabap.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/940036462b6f785a6abe00020432e330/tedimozifoz.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e3f798bde3---73552309056.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/dasizuworokinemapebalo.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/2iu29k40nhv770vtindg7qu5f9/sifipikedasilo.pdfIn PDF document text
    • http://inventory-acepipe.com/images/uploads/files/tofepuxu.pdfIn PDF document text
    • http://englandmatchshirts.com/assets/file/59843860127.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_off0000c4b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4B5 15832 bytes
SHA-256: d33f6c7cdfc1d395bc8d08fb7eb37ce7eaefb855260728392f64758d4a9ceb16
font_01_sfnt_off0000ed58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001056f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1056F 10964 bytes
SHA-256: ee2a30a775f3b80b9a7b0afa9cfb336d63db7da1d3b15367ea95360d4058a27a