Malicious PDF — malware analysis report

Static analysis result for SHA-256 77a0c8ce2904dfcb…

MALICIOUS

PDF

80.0 KB Created: 2021-07-02 05:37:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1be259aa02d242774858e21ab55007eb SHA-1: a34fa0c3f34e7a1811e6e26302bd114e722e4a8f SHA-256: 77a0c8ce2904dfcbb8e82966624da8f9068952edfc120120dbec3aeb011e4ffd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains a large number of embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious or phishing sites. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://synerhu.ru/uplcv?utm_term=data+mining+with+r+pdf PDF link annotation
    • http://inwallendorf.de/userfiles/file/87743482687.pdfIn PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/petifebunelig.pdfIn PDF document text
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/t10spo3aqodh29fhko6mg9ik9c/xumudesegavis.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/c314a1fcde0cbddf19236115608a3acd/32582854306.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160cc36a77dbb8---22130432884.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/dezavise.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/b7334e987efcdcc122bac94282adc7c8/kinixudutox.pdfIn PDF document text
    • http://wasserburg.pl/userfiles/file/33434834317.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/ckfinder/userfiles/files/moribe.pdfIn PDF document text
    • http://abwingsbuffalo.com/uploads/files/91852811407.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/ab9f7afa7762fa681120c42de4bafea8/wizabijigelakuxajojupomo.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/3jdclbss17a3aenhgjgj54mmk4/gigasupubumosolimadosir.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d1665850ee---zujutimakakuzijafevozupa.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/1e16bf33fb70f07eb3f8def8102ce23e/82045130758.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160807d9f692ef---97888912264.pdfIn PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/92732125243.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608a20f70cbe1---vozekudo.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-6/file/befudul.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077185327baa---toxoxik.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/ql9u2be2koa6dmedvgbn45qnh3/xuwusopiburubejometulose.pdfIn PDF document text
    • https://cdpu.net/wp-content/plugins/super-forms/uploads/php/files/a58ce9c7b2170cd6ddfd9b1e8cdcbe4f/xopaxajanawuxubazafofifu.pdfIn PDF document text
    • https://cremyco.com/app/webroot/docs/file/67392167419.pdfIn PDF document text
    • http://schokozentrale.de/idata/wukixamumapet.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a7b320d7607---joretibixixafevod.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ba193a15ede---30916403262.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/073ebdd51c98419cfcccfe539539abf7/mifadesiromipizajera.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_off0000d56b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD56B 17312 bytes
SHA-256: 52434361ee5d867edf185ff7f938c0ee89898c1ad5b07a2610e94c7d4933727f
font_01_sfnt_off000102f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102F4 10564 bytes
SHA-256: d553cb1efa5d0372284af86f6f15defe8becc2205ebde8bd18ec9e7d3791290a
font_02_sfnt_off00011aa6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AA6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1