Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc13e1a18105e2c0…

MALICIOUS

PDF

86.1 KB Created: 2021-07-03 07:26:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 18dcd0b27ecfe5805032fe1c993c89c6 SHA-1: 194ea4e066205b45b6a4de4d1520cd19571fd5b9 SHA-256: dc13e1a18105e2c0849bda8e00831817c3bfc5c246d9986862b49f1559b3c54e
156 Risk Score

Malware Insights

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

The PDF was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's designed to redirect users to malicious sites. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL analysis point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/qmcupvtruttuodi5sfqphnmqpa/81998408287.pdf
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff2ac34d1a---4801233892.pdf
    • https://susta.vn/userfiles/file/51423830783.pdf
    • http://status-go.net/gfx/userfiles/files/nebibaduzafadabe.pdf
    • http://ptairsupply.com/userfiles/file/belokiseb.pdf
    • http://peak-experience-japan.com/86879374080.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/1sh75k1mjltcqfieom8gee1nus/69301210713.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608a589d7197f---4555562919.pdf
    • http://huntland.hu/upload/file/65270865573.pdf
    • http://brnc85.com/clients/878796/File/48202249336.pdf
    • https://shreenathtechnologies.com/userfiles/file/95032741031.pdf
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160abf977c094f---fefibadijituratofidefuj.pdf
    • http://parejalecaros.com/adjunto/upload/fck/files/41035749482.pdf
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160856ef106dd6---taxefidozatuvo.pdf
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607da79b27501---27824524156.pdf
    • http://allseasonsart.com/uploads/fck_uploads/file/34233769611.pdf
    • http://infrabud.eu/fckpliki/file/titejex.pdf
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160737584a38d5---molebisopaf.pdf
    • http://gld-lining.com/user_img/files/3926542069.pdf
    • https://baileyelectrical.services/wp-content/plugins/super-forms/uploads/php/files/940i7358sp4p658mj5krrnoq0s/jutamatorarajebalez.pdf
    • http://prmakeup.com/Image/files/21500252615.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607615b73e311---zapijenukesufeb.pdf
    • https://www.sudburyhighspeedinternet.ca/wp-content/plugins/super-forms/uploads/php/files/0eaf52e602c2771bbb0f0d0ae6decd50/rutivotixodim.pdf
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ded2486ac50---80998272851.pdf
    • http://shophouse.info/images/files/gafivajifirosusivisiwaj.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=types+of+gentrification
    • 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_off0000eeed.bin
a2c738a9aea4c3c61aa1f525c9728f59cf62119b29cd4376412757d7d693fad7
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEED 16752 bytes
font_01_sfnt_off00011a6a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A6A 16792 bytes
font_02_sfnt_off00013281.bin
572c7210f6b999afcda4c2b0e81994be1d8dedd4f717d43e9bf2e2890b2bd887
pdf-font-stream PDF embedded font (sfnt) at offset 0x13281 10688 bytes