Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5044379f819e5ac…

MALICIOUS

PDF

75.4 KB Created: 2021-09-10 17:04:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 446e848b4940756257d2858d22cd013d SHA-1: 08f46f1dd697f8fb77ef40a1341aba5e815f7b16 SHA-256: a5044379f819e5ac899f7139528ac31782d7e46890f8726aebd441a855a84d6a
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://chcial.ru/uplcv?utm_term=repost+for+instagram+kimcy929
    • http://adbuilder.at/ckfinder/userfiles/files/muwoluteno.pdf
    • https://noihoithanhtuan.com/media/ftp/file/78886719447.pdf
    • http://xn--80aer5aza.xn----htbdepbihnfb8cyg.xn--p1ai/ckfinder/userfiles/files/69864048583.pdf
    • http://techbico.vn/uploads/image/files/59989379760.pdf
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613afbc3f0463---dolupadexufo.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132933be717e---pajiputesiga.pdf
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a80a1bfcc5---79705884135.pdf
    • https://footballsod.com/images/ck-uploads/files/78733126102.pdf
    • http://urs-certification.com/gais/image/file/91231730914.pdf
    • https://cicasoftavukatwebsitesi.demowebsiteleri.com/upload/files/97474646671.pdf
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/10029363a8110a877613dd87e7c6be25/pobajiras.pdf
    • http://kuehllawpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xemisugulusejotefizax.pdf
    • https://sportuna.be/ckfinder/userfiles/files/mitizine.pdf
    • http://xn--b1agpbmdtf.xn--p1ai/upload/file/nanilurowikex.pdf
    • http://hanahana.vn/media/ftp/file/duzuke.pdf
    • http://glovimex.com/uploads/ckfinder/files/26605185988.pdf
    • https://matrainagycsalados.hu/userfiles/file/gureka.pdf
    • https://totounited.com/contents/files/jutalodarixowuxamur.pdf
    • http://vietsinphar.com/uploads/files/88971900223.pdf
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/5a2f50e9684c1af9268b7486494f8576/jugudu.pdf
    • http://dui-antidote.net/images/userfiles/file/527349610.pdf
    • https://tavcam.com/upload/ckfinder/files/vaberusiwerejuvedoredemuv.pdf
    • http://arenabilardo.com/data/_files/tiwev.pdf
    • https://ismet.com.br/ckfinder/userfiles/files/72767302461.pdf
    • http://qbcar.ru/ckfinder/userfiles/files/nofidinikomijeg.pdf
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/26364e6f22cabb981aee6bd0d3e417de/pulumagopixinowevaxomilo.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c121.bin
b284fb9d54f34c5f1045249e719a2cd5039e24b20f8a2ba10f06fc5462e2517b
pdf-font-stream PDF embedded font (sfnt) at offset 0xC121 17016 bytes
font_01_sfnt_off0000ed0b.bin
27c6fbf6c876ba6ec2d33027758ae771baf8f0b56c2d55cd528e1388afe2b687
pdf-font-stream PDF embedded font (sfnt) at offset 0xED0B 11316 bytes
font_02_sfnt_off000107c8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x107C8 16792 bytes