Malicious PDF — malware analysis report

Static analysis result for SHA-256 9ac3a8bf72c0b4a4…

MALICIOUS

PDF

88.9 KB Created: 2021-08-03 01:09:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7558347dddaa6592235a1b97fb00b565 SHA-1: 9a394312a0146b447cf962ebbd08354ac8e82620 SHA-256: 9ac3a8bf72c0b4a4f38f655f634fb7696359459ab60f67ddbddb0ad84fd853a6
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is unreadable, but the heuristics indicate a pattern of hosting malicious PDFs on compromised WordPress sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://aylincinarli.com/fckfiles/file/fokoretobazasimali.pdf In PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf0f1831b4f---85420818454.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16080115e678c2---lalejujilurusokoduse.pdfIn PDF document text
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608406ab0e0c7---lojasel.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/f701205a746d325f0bced4d9e9702668/22208400998.pdfIn PDF document text
    • http://lacasedescaraibes.fr/file/12528624111.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c5976ac6953---medepesilibokisemonukux.pdfIn PDF document text
    • https://aydin-elektrik.com/resimler/files/25957844654.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad123060143---gopifoxibana.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/438kg6t2b0htgqvkcdo1upvb5m/pemiwotepamowosozunazujab.pdfIn PDF document text
    • http://uco-kampen.com/media/files/54360094374.pdfIn PDF document text
    • http://insfilings.com/skyzone_classic/upload/files/gorurivizapuviwidanig.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089708635214---zisixozutikupuvetobap.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/9272648503.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098260ae06e8---70785678333.pdfIn PDF document text
    • http://opuspointpartner.com/ckfinder/userfiles/files/24266732307.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160af439f0809a---64354207935.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3a4c7f029---69871065512.pdfIn PDF document text
    • http://bluecreator.biz/ckfinder/userfiles/files/papazusizeve.pdfIn PDF document text
    • http://sovaimm.it/userfiles/files/69853715792.pdfIn PDF document text
    • http://www.zdravotechnika.com/ckfinder/userfiles/files/murulawaledupadufeve.pdfIn PDF document text
    • http://xn--h1acbpobggs.xn--p1ai/data/files/dowiviwepagadezewigamopej.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/u0qde6kb5u9bevlu44jpn2el75/49974650823.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160799756dd2f7---videvegufofo.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a67bdebc0c---sabasupebuposupokid.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=why+the+rich+are+getting+richer+robert+kiyosaki+summaryPDF 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_off0000f5c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C1 17476 bytes
SHA-256: 91cd52e1e65af4d85d64e8e99ad05ded803168ae190684cd49058bf0361b2d4c
font_01_sfnt_off000122a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122A9 11068 bytes
SHA-256: 29d7c3f10074194f319b31afbd64507128a6638daf4cbddb8559cdf9fca625a3
font_02_sfnt_off00013c58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1