Malicious PDF — malware analysis report

Static analysis result for SHA-256 0fd4545ab2737406…

MALICIOUS

PDF

84.4 KB Created: 2021-06-25 19:46:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 150d95e045183c9250db330219237c5e SHA-1: 3800ec70e22210622b07475c07efaeb9ed0fe666 SHA-256: 0fd4545ab27374062b14dfbefa4cdd2119a5e23d112f579b55fa241b905a3f41
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic findings are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://royalrep.com/userfiles/files/83369115244.pdf
    • http://lynxitservices.com/ckfinder/userfiles/files/tojabatuv.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ebd11e8c64---18700262204.pdf
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d339eac89c---73775860245.pdf
    • http://immobilieninvestors.eu/userfiles/file/11419392333.pdf
    • https://adlinefor.com/home/webagen/public_html/korn/data/file/dotapazijajod.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c301a26444b---71427455520.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078a12e4b4cf---72463970235.pdf
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607519476fdbe---37561750997.pdf
    • http://valsadindustries.com/userfiles/file/vivefobutuzenabonukasog.pdf
    • http://wenxuezj.com/images/File/87899211911.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e486c99f6---jeninutu.pdf
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aec8f77533---selada.pdf
    • http://sistersaviopublicschool.com/userfiles/file/votutawoneveronigunateg.pdf
    • http://akcjonariusz.com/UserFiles/file/84575434460.pdf
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/067d34ee6deedd42048023856894b283/mefugegaxiv.pdf
    • https://campermagazine.tv/public/file/30722073227.pdf
    • http://bakoca.hu/files/file/10664350147.pdf
    • https://xistenze.com/files/files/30721705036.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160700f240abe7---fuxagoneremip.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c9ed6178cbb---24367709453.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/abjpg15cqe2iarsfie02sgj9su/75471900851.pdf
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f82378744e---94303552796.pdf
    • http://msslink.ru/userfiles/files/83085208707.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=what+is+unremarkable+mean
    • 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_off0000e9a3.bin
9436e8d4a8aa72d629127c07d051658e9ef01347d640d2def220cf05801d4588
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9A3 10580 bytes
font_01_sfnt_off0001019f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1019F 16792 bytes
font_02_sfnt_off000119b1.bin
2b5070d7519a84051c1c4b8d7c71246e0863201df18bffc40292566a18184df4
pdf-font-stream PDF embedded font (sfnt) at offset 0x119B1 16508 bytes