Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c775a4e8405539f…

MALICIOUS

PDF

74.1 KB Created: 2021-09-03 07:52:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 6238f6444533643b8b7efda83e21c80f SHA-1: db0f30e2f68ab80ecbf135661054ca88c5840b35 SHA-256: 3c775a4e8405539f65b57b6b18683394e1743d0571c26a4f9429dabd94d146fe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm or phishing lure. The presence of embedded URLs and the nature of the heuristics point towards an attack pattern focused on redirecting users to malicious content, potentially for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9914

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://philabc.ru/uplcv?utm_term=dstv+wifi+connector+user+manual PDF link annotation
    • http://kientrucphatloc.com/upload/files/kijusejomiwotepujoduzajoj.pdfIn PDF document text
    • http://lotusromeo.fr/app/webroot/files/userfiles/files/99821882537.pdfIn PDF document text
    • https://projectmine.hu/ckfinder/userfiles/files/xokolufofijasesan.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7fe3656af9---pojajibidow.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/5cjrku23kfma26qj5qu45piipn/vigawojizodunaz.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/kvdlt7rgena4u3i9b0qcnovur1/wekesubajerobutegesu.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/luwipegedusomede.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/5bb9985f470f4cbe07e2086c1db09e38/6811377505.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd5ed79a9d0---6488007694.pdfIn PDF document text
    • http://futurepoolandspa.com/ckfinder/userfiles/files/24794863443.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/91d9313ceafc27eabbeb9795d13c2da1/31899286186.pdfIn PDF document text
    • http://arcenevents.nl/site/upload/files/70515594328.pdfIn PDF document text
    • http://asvpp.fr/pdf/44603398282.pdfIn PDF document text
    • http://madveras.com/ckfinder/userfiles/files/sunupepelubejifo.pdfIn PDF document text
    • http://lawngo.net/fckfiles/57195791319.pdfIn PDF document text
    • https://digireg.ch/upload/40349313667.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1384436c8e---purunodu.pdfIn PDF document text
    • http://renovator.cz/files/file/gulinorixulokir.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/e9310856741d8e825f8068949f7305f6/gopavutizufujawa.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/wugorizimurogaxu.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/noajg8555gteac5a8p2vi73au3/jirefubininagusite.pdfIn PDF document text
    • http://artgrafika.cz/userfiles/file/najejiwuvutowatinole.pdfIn PDF document text
    • http://www.photonics-science.com/ckfinder/userfiles/files/23613917899.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/nuxiruwipezobowugosidadix.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/6q69rnnlaof70lfmko7d4nka7r/tanurezusepelifob.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2e9b93a16b---tirinexisifumis.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_off0000bfab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFAB 10752 bytes
SHA-256: dd1c0ecba3b03d3a93664ec91680b7a429cf2c08302c5ab4846480967ce2b346
font_01_sfnt_off0000d87a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD87A 16288 bytes
SHA-256: c8d814fb5534a5c06e9409447e5188743c20766cb7415cfc6437e1539fb4aceb
font_02_sfnt_off00010265.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10265 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1