Malicious PDF — malware analysis report

Static analysis result for SHA-256 1851f7dca583296c…

MALICIOUS

PDF

80.4 KB Created: 2021-09-16 11:21:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b9d9631691a0e4670921c1e3bc6199a4 SHA-1: 2577c649df8a9433bfd3b8fccc4040737c4e5e76 SHA-256: 1851f7dca583296cc65a8749471ee044a18fa5b5cdfbecd9bc6841b7e37bf572
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm directing to numerous URLs, several of which are hosted on compromised CMS platforms, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, with the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supporting the nature of the content. No scripts were extracted, but the structure and URL analysis point to a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://www.deco-interieure.com/userfiles/file/40642941558.pdf
    • https://pamukoglu.com/userfiles/file/guxurubitifexigimuf.pdf
    • https://www.stnedu.com/ckfinder/upload/files/tixetixe.pdf
    • http://www.cenlajobinator.com/siteuploads/editorimg/file/gafupe.pdf
    • http://stonepigments.com/userfiles/file/21964830758.pdf
    • https://ita.kru.ac.th/ckfinder/userfiles/files/66499477392.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ecc26df6ef---topanexibudav.pdf
    • https://nguyenthelong.net/userfiles/files/luninowudigilap.pdf
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613eb4d8acdfd---mamunefesul.pdf
    • https://pass-eco-energies.com/ckfinder/userfiles/files/tuxupojukuzebizurilawilef.pdf
    • http://gsemilia.it/userfiles/files/darajumevovamore.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/75b0bvdqanode9auru2kkd23hc/79842010676.pdf
    • https://filetorme.com/upload/files/mobesimebani.pdf
    • http://jolanyee.com/upload/files/202109140203286956.pdf
    • https://sportnazona.bg/f/uploads/files/vusadugazotatixodijaxuf.pdf
    • http://evohome.pl/userfiles/file/sixegepagora.pdf
    • http://tareeapartment.com/user_img/files/munaxeroz.pdf
    • https://mangallagn.com/images/file/vagag.pdf
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/56cbf323fe43ad4b219d28699d8ad574/63728850899.pdf
    • http://elitaliaweb.it/upload/file/fojuxuseki.pdf
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161407e22ebe69---92621532254.pdf
    • http://lnv-cnc.gr/userfiles/file/gapawogowuj.pdf
    • http://artin-intranet.com/ckupload/files/regevoguzubunasad.pdf
    • http://hardiebase.com/uploads/assets/filefile/masuvirenuxadegexigab.pdf
    • https://nergizleryapi.com/image/files/70606834417.pdf
    • http://megalaserasia.com/upload///37647781836.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=s20+ultra+ui+3.0
    • 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_off0000d63a.bin
0fd7868147677975041ac0289387b21579d34ddf2c2f863678a7f3442cd14086
pdf-font-stream PDF embedded font (sfnt) at offset 0xD63A 10232 bytes
font_01_sfnt_off0000ed67.bin
1803a4bffdee11f0626db4ed539f1805999dd6c3d89665cad9e91e9babc19ec3
pdf-font-stream PDF embedded font (sfnt) at offset 0xED67 18088 bytes
font_02_sfnt_off00011c2a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C2A 16792 bytes