Malicious PDF — malware analysis report

Static analysis result for SHA-256 987e4e3e3f8458cc…

MALICIOUS

PDF

118.6 KB Created: 2021-08-01 18:41:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 39142f7bcdd09e3365d09e430849c036 SHA-1: 20410255858541ea171a995cfdb63cfca16d18a1 SHA-256: 987e4e3e3f8458ccb93980d340b406c561a03b779f708448663f470904d658a7
156 Risk Score

Malware Insights

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

The PDF was flagged by ML and ClamAV as malicious, indicating it likely exploits a vulnerability or contains malicious content. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external links strongly supports the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 http://asijskepotraviny.cz/files/file/lijagomusamud.pdf In PDF document text
    • https://ltanimalpark.com/wp-content/plugins/super-forms/uploads/php/files/e7b9e1cc69d40675d1ac98d454e4b6c6/36383896434.pdfIn PDF document text
    • http://www.haztartasigepszakuzlet.hu/pics/file/7098072267.pdfIn PDF document text
    • https://www.zaantraining.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b989f182602---lakidixa.pdfIn PDF document text
    • https://najlepsze-w-polsce.pl/uploads/rotezibozejivuwiwi.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/1d0cba41b0db4d22b7f498a3c3a92afc/38577220283.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/a3452c7989b788974b5ede18264fd007/55157522094.pdfIn PDF document text
    • http://notarbrazda.cz/userfiles/file/vasojitonomosexupigefu.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16082ca7c47732---rumobewiwalitutilalojezoz.pdfIn PDF document text
    • http://findmealocalpainter.com/insurazon/admin/userfiles/file/wixatobelasedupuwife.pdfIn PDF document text
    • https://flexi-cms.com/uploads/file/39475864255.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609effd6a81fd---domerede.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607895b8cc373---60398123121.pdfIn PDF document text
    • http://www.monts.sk/upload_images/file/fakajasebu.pdfIn PDF document text
    • https://ustunbilgisayar.com/userfiles/files/gukowelirunupugedafe.pdfIn PDF document text
    • http://sun-tes.ru/files/file/kimugoxos.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c692425c13---bibefesekemiwolevobidoni.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/82c336c6fc7de9632f02cc61758034ed/48694176864.pdfIn PDF document text
    • http://www.emailposte.com/pictures/73449481013.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/g0s60e3ss4538smg4pae2ivkb7/gelejediwifovanawizaxi.pdfIn PDF document text
    • http://triyoga-tv.ru/userfiles/file/11823627938.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609866011d6ac---98790000626.pdfIn PDF document text
    • http://kme-kme.cz/files/file/wapuzosi.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a37e320a3b5---gufedep.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608fc87e16e98---vevekunexofepomav.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=puppy+running+in+sleep+daily+mailPDF 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_off00016da1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16DA1 10732 bytes
SHA-256: b135c46722068994f6060211dedda0222d78edce7a1507862d153c91f35dda2b
font_01_sfnt_off00018601.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18601 17712 bytes
SHA-256: 9b7a6346ad6d3e5223160689c03506834e2a3383dee51a89d50df57d19082565
font_02_sfnt_off0001b416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B416 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1