Malicious PDF — malware analysis report

Static analysis result for SHA-256 7ef9eff1f389a2f4…

MALICIOUS

PDF

68.4 KB Created: 2021-09-25 23:53:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1b18fe724627cc427eb9cb5579a379ee SHA-1: 22c331dd6ce84398e79d538cb696e1d79586d24d SHA-256: 7ef9eff1f389a2f40a8f4df542082d1aa28634cf510b072be9159732eae6c36f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e2b0b8c480---fifodos.pdf
    • http://bharatdarshan.net/rgroup/ckfinder/userfiles/files/18443396636.pdf
    • https://thokhoavietnam.com/upload/files/33593992278.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/2956b4f8f296517f4cfc142282dd5e91/38761951321.pdf
    • http://unite-chem.com/upload/files/83145238083.pdf
    • http://osingenieria.com/images/admin/file/vudinus.pdf
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16149716c3a011---xododegekelujamugoko.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/27cc900792dcbe2e075d2fcbbab649f6/4645525427.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a13cf1ab64---10899053591.pdf
    • https://invest.pl/userfiles/file/defixafepomorore.pdf
    • https://egyiksem.hu/uploads/file/bivemanetebazufe.pdf
    • https://vayamcs.com/content_files/files/xogudigitadoxelozudenov.pdf
    • http://ahcxdq.com/uploads/file/081819093997.pdf
    • http://touristclub.in/userfiles/file/14223358626.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16140d4c3e8e6f---zalekulagudikoxuki.pdf
    • https://fishuntpesca.it/file/71421590583.pdf
    • http://prinsart.ro/uploads/files/ludipisatifubokowelunosoz.pdf
    • https://www.travelknowhowscotland.co.uk/assets/js/ckfinder/userfiles/files/28734414539.pdf
    • https://aventura-agence.lu/userfiles/files/tujufosemoru.pdf
    • https://juhaszautovill.hu/userfiles/file/28180138546.pdf
    • https://abzesolar.com/uploads/files/62940278514.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/dfs7fdacjcvfgipscbq4k4e49k/94314092542.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=night+hunter+watch+online+free
    • 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_off0000ae0c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xAE0C 16792 bytes
font_01_sfnt_off0000c623.bin
75bee4965aa137a9dbed45d91707ea73ad362f595eb1a10d43de517646a6ebec
pdf-font-stream PDF embedded font (sfnt) at offset 0xC623 10608 bytes
font_02_sfnt_off0000de67.bin
35b65563e0dc811fb03dc723083fa3476136209d13b55b92f78bb2819bec5f0d
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE67 15060 bytes