Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbda82fb3431ba2c…

MALICIOUS

PDF

145.7 KB Created: 2021-07-04 11:32:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 436c1df21d24aa2f70b1c4a4bf294fb1 SHA-1: c76283337991239d3889f9ffb3d43a799d728f49 SHA-256: dbda82fb3431ba2c0fa4bade8456f2efeef93389eb3672e111c6f6c090fbcf1a
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to obscure malicious destinations. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the link farm heuristic and URL analysis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9920

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://aspaeng.com/files/image/files/12660192311.pdf
    • http://asahiru-ban.com/files/files/18222262337.pdf
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/939c47760f564a649aa5e4718ddf877d/26708696199.pdf
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a06f80ce7bb---94377022180.pdf
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/840fe96704d6a8453ab7db821af07567/94030067489.pdf
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/t4tr93v983mj92e51veo0ihdjb/26350901147.pdf
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/pii2mha81a8tldfu2k6tth059b/69359592554.pdf
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/cfdf2f528bc06a628df75d58a06769c3/nisakatusolukugun.pdf
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ba016dc35dd---99662198559.pdf
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/ju5uge714mspqm9f2m94g2ii7q/tikexaxobitepop.pdf
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8c6a48dc72---pupalajedinafoditujusiwuj.pdf
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160aa50a9789e8---piferugivafuxuxora.pdf
    • http://tunglamgarden.com/images/fck/file/84624870666.pdf
    • http://s8radziejowice-paszkow.pl/userfiles/file/jezipegonasomigebosagise.pdf
    • http://pytextiles.com/userfiles/file/gafonazanada.pdf
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/lmnk2ubsffsg8f7svoa7tegg92/22308912281.pdf
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f744100043---dotoro.pdf
    • http://sme1970reunion.com/clients/7/78/786f1e38e9ed540b4a7d4f5dbcc09398/File/rulawep.pdf
    • http://wirheiraten.de/images/file/mozawivovivusigexot.pdf
    • http://www.jucadent.es/ckfinder/userfiles/files/23987220883.pdf
    • http://newgrids.com/userfiles/file/doromawafa.pdf
    • http://biosite.ru/images/news/file/momixezeridapukijisujina.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609abc390318e---bawewegizitom.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=croup+viral+infection
    • 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_off0001d97a.bin
5bc1a242faf11d2e90ac8a160c8e0f92211b2bf086e5c5c8057aa613fe4bdefa
pdf-font-stream PDF embedded font (sfnt) at offset 0x1D97A 10504 bytes
font_01_sfnt_off0001f180.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1F180 16792 bytes
font_02_sfnt_off00020992.bin
f11cc859ef3f84f56ea90ef2fa77c043e79e9693e00dd81bee03238351677c2d
pdf-font-stream PDF embedded font (sfnt) at offset 0x20992 18312 bytes