Malicious PDF — malware analysis report

Static analysis result for SHA-256 d756f72d77cb63ec…

MALICIOUS

PDF

69.8 KB Created: 2021-09-30 11:47:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5131c27db52276cf97f3fef9de9532a2 SHA-1: e340e9ed7bfc9b72ff8ddb326c42bb5b9bba0487 SHA-256: d756f72d77cb63eceeb49a7b30794812529d3d1d076497ed7433590015977038
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on compromised or disposable domains, indicative of a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://cructi.ru/uplcv?utm_term=free+fire+in+pc+apk
    • https://leciv.fr/uploads/FCK_files/file/1394728586.pdf
    • http://ulrike-mayer.de/userfiles/files/xowisuk.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161414694f278c---98175182240.pdf
    • http://cartopack.be/Images/file/48899727349.pdf
    • http://auksozvynas.lt/userfiles/file/womozabelomipos.pdf
    • http://jdjcnc.com/upfolder/e/files/20210907213241.pdf
    • http://wsp.pl/userfiles/file/6568392970.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/cf8d43678236bbdb1f16cc87cc7afa7e/tijunofikolorim.pdf
    • http://zaiger.ru/img/file/54911931357.pdf
    • http://grgct.com/ckfinder/userfiles/files/7306819532.pdf
    • https://tectrongim.com/uploads/file/xelisab.pdf
    • https://glaze-metalart.com/upload/files/golixenuxubipibuxubogizu.pdf
    • https://eletroluz-al.com/_IMG/img_internas/file/jidinaverozigunulizol.pdf
    • https://thefertilizerequipment.com/d/files/34711979448.pdf
    • https://kipass.fr/userfiles/file/tozotunusizesawepoduk.pdf
    • http://kes.org/upload/editor/files/duwez.pdf
    • https://www.ccs-corporation.com/ckfinder/userfiles/files/16493630159.pdf
    • http://cherriestattoo.com/ckfinder/userfiles/files/vagotedavogopali.pdf
    • https://ww150006.linebot.net/upfile/files/20210918152454.pdf
    • https://dukeofmarshall.com/ckfinder/userfiles/files/vuzijamebazixilatitu.pdf
    • http://constantcontinuity.com/membership/data/files/godukofitifokamofa.pdf
    • https://oazapiekna.com/zdjecia/fck/file/liduwo.pdf
    • http://minhledtran.com/luutru/files/pusudeboraponotowotonadu.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/161367202a68f3---lujovixefogelolipuxuj.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_off0000b2e6.bin
3d2a36fd48ff2764bfce8511a56634e46e25569cddf3f0ad7c52299d744757a5
pdf-font-stream PDF embedded font (sfnt) at offset 0xB2E6 10112 bytes
font_01_sfnt_off0000c97f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC97F 16792 bytes
font_02_sfnt_off0000e191.bin
37bb2f0659d4fa1a3cbc6ec0ebcb5d011e2d7ae5edc90a3534c4d010caff1efc
pdf-font-stream PDF embedded font (sfnt) at offset 0xE191 15724 bytes