Malicious PDF — malware analysis report

Static analysis result for SHA-256 0021c0542a4ecce8…

MALICIOUS

PDF

78.5 KB Created: 2021-07-19 10:30:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: bfddb75fdeb3b6f7fe81b751cccad7d5 SHA-1: c33303ee062b0abe229b7e1e6d51883a7011f02c SHA-256: 0021c0542a4ecce8eea9c2d9d91ee1903c185998db1fcbae30132de72b2eb790
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous links pointing to external websites, many of which are hosted on compromised WordPress sites or disposable domains. This behavior is indicative of a link farm designed to redirect users to malicious content, likely for phishing or malware distribution. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://atek-ent.com/upload/file/muzopumajogenasabo.pdf In PDF document text
    • http://piazzademarini3ge.com/userfiles/files/barasosakijejon.pdfIn PDF document text
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/78r2051k6kbujqo55kesh3s6t8/18433760984.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/14682f7d31c438733ea97b90bb9443de/15200341081.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1d52f92a19---xaxap.pdfIn PDF document text
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/d178cddf5b06cb9637fb87ef1c945d86/7188835290.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a37382a8363---kajeraji.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/68015427653.pdfIn PDF document text
    • http://casier-a-bouteilles.fr/file/bopalada.pdfIn PDF document text
    • https://promise-land.com/upload/file/vapotepobeziruwa.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607e40dd78602---78576101372.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/c6def8d04695792219d5cb497ebb03b1/8611061326.pdfIn PDF document text
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/tdj5o1cjr0omn7ft76igo66v98/xesenu.pdfIn PDF document text
    • http://bowlinggreenhsclassof66.com/clients/b/bd/bdf8ab256cd88a603fc2b95a051c5839/File/75462296423.pdfIn PDF document text
    • http://big-blue-bus.com/pics/fotos/1/file/kevanodap.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/92970017268.pdfIn PDF document text
    • https://www.rongoldmanlaw.com/system/js/back/ckfinder/userfiles/files/pogibemusakipu.pdfIn PDF document text
    • https://tekmaker.com/upload/files/gopepawidofiviliruniras.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075537360ea9---lalalakurujulax.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16071a0b06779e---xomibujuxepidok.pdfIn PDF document text
    • http://takeacode.net/user/d41d8cd98f00b204e9800998ecf8427e/file/judutawimepiwikim.pdfIn PDF document text
    • http://adams-gold.ru/archive/image/file/zaxomelexobedu.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/t10ueh61ch1q4ln3at1ttuggb1/sopotevenutozegip.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/837004078d112001406938773dd558b3/xemoxuduwu.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ba1ea0542af---30443930789.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=to+determine+the+resistivity+of+semiconductor+by+four+probe+methodPDF link annotation
    • 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_off0000cf7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF7E 16496 bytes
SHA-256: 6efe8ac8c2aaa66d7b5253c5b050961fb4c3b5cee2978170ebe54139c525cd87
font_01_sfnt_off0000fa66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA66 11060 bytes
SHA-256: ca0f65c4eb9dd834ec2b672fb3da5d78d3fff142c73baee84f16c729f484c920
font_02_sfnt_off000113c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1