Malicious PDF — malware analysis report

Static analysis result for SHA-256 af2ef571eef93880…

MALICIOUS

PDF

97.5 KB Created: 2021-06-27 06:06:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2626abd0dd32d98d70943ccd16e49191 SHA-1: 4792191f6e249cacc2961262efd344d1f8ac4d60 SHA-256: af2ef571eef93880557fe321c4cb77a027b132ee1d7ac5ecd357c77eb2ee1310
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to various websites, many of which are hosted on compromised WordPress installations. The heuristic PDF_RANDOM_URL_LINK specifically flags a link to a PDF hosted on what appears to be a malicious domain, indicating a likely attempt to distribute further malware or conduct phishing. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://coretry.ru/uplcv?utm_term=computer+fan+airflow+direction
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/adqoei9k7hai1nv5olgjb0o895/9469597796.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7939acd42---tipudusotalubi.pdf
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160922d9f0b162---pivukiluteret.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/of1j21j6sm2hro19rhn7s1jvfs/72055552916.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/95581becaeb93ff0010c790167d069ab/jilid.pdf
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/e83340ba0df92f3489f7fa14710b6820/zugetibadajifugis.pdf
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/559088ce4af7730a717d8852bc5f2a03/45781059920.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/90j7nc7ek9ds8u4l5lldmdu5c7/17224299728.pdf
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ba0d85cc8b---xebibabajezugunezaludi.pdf
    • http://bigxra.com/uploadfile/file/2021051923155573499.pdf
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607725489537c---mexoz.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a4b1f3abd67---54345450027.pdf
    • https://transit-connection.com/userfiles/files/gikaxot.pdf
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087a2f31ff6c---sorolut.pdf
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/1d31c12ac9b8047cbada10c0d8d6d8d4/jovoborew.pdf
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a2ee1150b12---wirubulobivokijoxomige.pdf
    • https://airflow-skateboards.com/upload/file/girufeje.pdf
    • http://backkwang.com/userData/board/file/sudunene.pdf
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/87d667c8b820bcdf613eeeec7c52c5b5/66674028128.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1606d287730d08---liwugabinulezakefidina.pdf
    • http://pamat.ro/UserFiles/file/mokolevalerujefuluta.pdf
    • https://krono-original.vn/Images_upload/files/deviwujotilorenijijavek.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb7af6b0088---2839910169.pdf
    • 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_off000117cd.bin
320851f111712922bd2c09f3eca52d3011210a28e86d6129fbe771b63ae341e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x117CD 18188 bytes
font_01_sfnt_off0001478c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1478C 16792 bytes
font_02_sfnt_off00015fa3.bin
2bdf3669620e45dc97ec0a40eb80567f4c5887d1de13c7cbfab3a82a30d9b15e
pdf-font-stream PDF embedded font (sfnt) at offset 0x15FA3 10832 bytes