Malicious PDF — malware analysis report

Static analysis result for SHA-256 592b580680d045ef…

MALICIOUS

PDF

75.0 KB Created: 2021-09-11 13:41:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ba4ba79af2ab3e4153cdd4a681a15c4f SHA-1: 86c96c5abf7b2e887e6fe526500ef2474083e224 SHA-256: 592b580680d045ef0c61309885bb64d3dcb8c21d7549bdeb22d01c8b4c9a6085
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs and links to compromised CMS upload storage and disposable hosting, indicating a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, suggesting it is not intended for direct user interaction but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 6

  • 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.
  • 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://allytemp.ru/uplcv?utm_term=load+html+file+in+webview+android PDF link annotation
    • https://ibliberia.com/ckfinder/userfiles/files/begokiviputasufixixev.pdfIn PDF document text
    • http://valentine.tutaylamhet.com/storage/ckfinder/files/21628182575.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/e5n30l6ovngvkha54nhrr98uc3/zofafipomur.pdfIn PDF document text
    • http://mengnuanua.com/app/webroot/files/files/butejibizuvove.pdfIn PDF document text
    • http://discus-rus.ru/upl/file/segufenerekuxotazu.pdfIn PDF document text
    • http://kronospan-mofa-hungary.hu/editor_up/51686280835.pdfIn PDF document text
    • http://vin-baietii.ro/ckfinder/userfiles/files/33844541088.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613997ab58fa3---84040863055.pdfIn PDF document text
    • http://dsagco.com/Upload/file/3712836636.pdfIn PDF document text
    • http://architettodrabeni.it/userfiles/files/zesameviwugeje.pdfIn PDF document text
    • http://marymo.ru/uploads/files/gemizosazabin.pdfIn PDF document text
    • http://kaie.org/userfiles/file/20210909235634.pdfIn PDF document text
    • https://home-consult.lu/userfiles/files/puvobakixikuzex.pdfIn PDF document text
    • https://suprizpin.com/calisma2/files/uploads/76934092448.pdfIn PDF document text
    • http://materialdeestudo.top/userfiles/files/livoxitulopinugiderig.pdfIn PDF document text
    • http://labellebeaute.com.hk/ckfinder/userfiles/files/41101354927.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/16134ca5e05c7a---20224566206.pdfIn PDF document text
    • http://tutaylamhet.com/storage/ckfinder/files/nizudixofezabiritoso.pdfIn PDF document text
    • https://karapinarinsaat.net/userfiles/upload/file/sojuvibetugo.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613979845295a---84656599947.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16137f031a4d27---93054541452.pdfIn PDF document text
    • https://foodexgida.com/uploads/files/83092754924.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161358244b5b75---84847678640.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/gefiwefazomodadetum.pdfIn PDF document text
    • https://mobiligennari.com/userfiles/file/57212254694.pdfIn PDF document text
    • https://www.rt9.rspo.org/ckfinder/userfiles/files/40375028350.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_off0000c376.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC376 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB8D 10700 bytes
SHA-256: 47271e1d8f0b849c9be715de4932d0081209603ec5c26b4fae8fb7ed8b37e8f0
font_02_sfnt_off0000f3da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3DA 16308 bytes
SHA-256: a646be85eeaea70c61cdf222956d3882fde66b226979fc82bab54399ab915f94