Malicious PDF — malware analysis report

Static analysis result for SHA-256 a54cf010a1237840…

MALICIOUS

PDF

86.7 KB Created: 2021-09-07 23:37:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b84d74c880b60d7b3bbc8d992f7a76cb SHA-1: 214ae046a79af66f04d6c02ad4dde49124c39754 SHA-256: a54cf010a1237840b8cdca43f2760be7eae6e450ae34bd94221f7249f99b7066
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress upload storage, with numerous distinct hosts and URLs. The document body is heavily obfuscated, preventing analysis of its specific content, but the overall structure and URL targets suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609c358704771---99306151984.pdf In PDF document text
    • https://coastalstudio.com/images/main/file/jozeg.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/fopunemetisad.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/zebexujokefubekafeb.pdfIn PDF document text
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/d1b138a0e0721ad962e96f5a62be4cd3/86671796022.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/fatep.pdfIn PDF document text
    • https://bakotech.at/uploads/ckeditor/files/favalunevapubedalitu.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9916f3e559---94853152463.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/295a2cfaf0895269e9555c9c88ed8011/gupemodabawurametim.pdfIn PDF document text
    • https://nieruchomosciturystyczne.eu/files/file/78938147476.pdfIn PDF document text
    • http://domusanna.it/userfiles/files/96163943276.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16116260001091---noxak.pdfIn PDF document text
    • https://smilepath.com.au/wp-content/plugins/super-forms/uploads/php/files/14b7fda01d8abc494d1dd07a2e1e3aad/gujemomaz.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/modinagojezepezupa.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/os2n9qe3ti75fjriphsn9vu6e1/wawegemafejumewokoziwip.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161095daa23643---loxilobimuxudokavolexipe.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a634461bead---xixukugisuxuvusumibis.pdfIn PDF document text
    • https://666666.vn/upload/fck/file/33670339378.pdfIn PDF document text
    • http://chicohigh1987.com/clients/47015/File/dadagufapefakirunalidutex.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/wakifamot.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/634601d2d621f69e95f7f329158cfb1e/fifonifo.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/70275524508.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/41e9d4bc86311b36709aa1f4f4d418f8/71079125525.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/5b6637afdbd869f32b16ea75a46c3a74/sidagemun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=dell+inspiron+15+7559+service+manualPDF 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_off0000ea52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA52 11008 bytes
SHA-256: c572791c000e6324cf54a6f7e21a228abd0f61f345cabd136ae806a1d456b250
font_01_sfnt_off00010412.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10412 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C24 18696 bytes
SHA-256: 9428219bfd58b64e6ef57b2114075e20066ee2b02bd7016d4de83adfd222bea2