Malicious PDF — malware analysis report

Static analysis result for SHA-256 7760dde1b01eda42…

MALICIOUS

PDF

81.6 KB Created: 2021-09-03 06:38:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a92fa18c3bd25b4830bc08612d74f1ba SHA-1: 62d71dda942142c75780f1ec848fa61a7863c5ed SHA-256: 7760dde1b01eda423346ab6f8f3ed3a915371194d0c9154cbc85a9e6710b4b3c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links to external PDFs hosted on various domains, some of which appear to be compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links and the overall detection indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://mkycc4.com/kycc4.com/userfiles/files/gunikutositininif.pdf In PDF document text
    • http://ebiocell.com/uploadfile/file///2021071709243617.pdfIn PDF document text
    • http://fuzoku-kyujin.jp/ckfinder/userfiles/files/57880801442.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f411b01da4---23566143417.pdfIn PDF document text
    • http://superplasticizer.cn/d/files/zadatevonewel.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-8-7/20210807061758105297.pdfIn PDF document text
    • https://bevillelecomte.ovh/ckfinder/userfiles/files/rafewenuva.pdfIn PDF document text
    • http://tzoetemondje.be/uploads/files/jimifibevobireseziki.pdfIn PDF document text
    • http://thamdinhgiadaiquang.com/img/files/jifuxoj.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f2e620a85af---vopapa.pdfIn PDF document text
    • https://jasmijnbloemengroen.nl/userfiles/file/vumelesu.pdfIn PDF document text
    • https://xn--nmqu14inmf.com/upload/files/gobiwimapirisami.pdfIn PDF document text
    • http://stasta.com/userfiles/file/mamisab.pdfIn PDF document text
    • http://aklond.com/UploadFilesfile///2021042910452010.pdfIn PDF document text
    • http://yer-krasnodar.ru/ckfinder/userfiles/files/zizeviguv.pdfIn PDF document text
    • https://harom.ro/files/file/39122047322.pdfIn PDF document text
    • http://mai-colle.jp/userfiles/file/pofek.pdfIn PDF document text
    • https://londonvipchauffeur.co.uk/wp-content/plugins/super-forms/uploads/php/files/71565f06e2ff4ffac111f090fc8c4449/soxolulivezeribupilaburu.pdfIn PDF document text
    • http://delve-cr.com/uploads/11581644502.pdfIn PDF document text
    • http://ellev.fr/upload/files/konijubiw.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/zomekebogifegoda.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/a9cbf6c6331ac6bb6b428a954a7560d9/53001407343.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a2733f10386---31865449829.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091f48c26c96---75566946651.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=naming+bases+worksheet+pdfPDF 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_off0000d80f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD80F 11196 bytes
SHA-256: ab7db6652cd6e38891560f60f53dd6352fce55fae9407794ecc13d3a9f2dbdcb
font_01_sfnt_off0000f1bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109CE 18224 bytes
SHA-256: 1db287cbb96c2cea0ec8062bb8510e9bb9cc2ecef460f832ab115ab799f9b152