Malicious PDF — malware analysis report

Static analysis result for SHA-256 36a5955e33639a1c…

MALICIOUS

PDF

67.7 KB Created: 2021-06-05 15:18:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 5142450615fbdd3f76f0d8cffdc5a8a1 SHA-1: f0c9f2f34091a7e2d826460c4c70b3508f42e3ae SHA-256: 36a5955e33639a1c67fda59866ec8a37d34268c5da6fba60e4f5c2c859f59531
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS upload storage, suggesting a phishing or malware distribution scheme. The document body, though truncated, includes a title related to 'self appraisal report' which is likely a lure to encourage users to click on the embedded malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nomylo.ru/uplcv?utm_term=how+to+write+self+appraisal+report PDF link annotation
    • http://geoodwierty.pl/files/file/benilijoro.pdfIn PDF document text
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/aca1ee6ae514f08b0005bc5cd108a558/43921112788.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b005a326044---33791191363.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606cadf2ed30b---fifagejutojiribes.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc5a6eacd9---xegurudowagazepul.pdfIn PDF document text
    • https://finances-canada.com/wp-content/plugins/super-forms/uploads/php/files/74bc550389fb40fbdc576c11699c54de/78356825595.pdfIn PDF document text
    • http://asiavent.com/UserFiles/file/%5C/52397811126.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/7eda19e8d91311dc3ae49c0c3c9fdf98/24240234478.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5bd6250ed---zurisukupefotegig.pdfIn PDF document text
    • http://www.ecostroyservis.ru/File/wepatul.pdfIn PDF document text
    • http://elsekmont.eu/userfiles/file/kubajukogepipemot.pdfIn PDF document text
    • http://ebslang.net/_UploadFile/Images/file/mukoziwagaxediwoneve.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16085ce2029ee8---8420080623.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/0ad826cccd386f2c76ea9821ffaec9f4/funeralonizawerebajekojo.pdfIn PDF document text
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/9b96b8fc124d102c4631767d4501bc7e/vogiketi.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/7e3r5hi7sn0om6o046avjo91j6/93948170334.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/71382788824.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a919b28f9d0---xodapokatipabe.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF9E 4948 bytes
SHA-256: 1fd36d70a49c805a776ff1c3c7963f9bf4f4f8237303f086e6793a72bb415f4a
font_01_sfnt_off0000e092.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE092 9780 bytes
SHA-256: 280792056089b9e8351a2092a1c7b7b7774a692a230b4d83c75a6fd88430f14e