Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1d3cbbb7262a363…

MALICIOUS

PDF

86.5 KB Created: 2021-09-02 07:21:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6dcafc1ae13e1bc2dd0477d310cdc999 SHA-1: 9a3f92871ff0eee6d944fdfe3ec374528b61e287 SHA-256: c1d3cbbb7262a36382d121af0724e709334b5b06a80d79799e4a190559a2c670
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as a phishing trojan and by an ML classifier, indicating malicious intent. It contains a link farm pointing to multiple compromised WordPress upload directories and disposable hosting sites. While no scripts were explicitly extracted, the PDF structure and URL patterns suggest it is designed to lure users to malicious content, likely through a phishing or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://tort-art.ru/userfiles/file/nifulijudebogeno.pdf
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/bdb7e5effee055790c8f64d68f18976c/42302116115.pdf
    • http://bigxra.com/uploadfile/file/2021051007032373499.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16079753dc3914---28487309205.pdf
    • http://mywayrtk.info/userfiles/file/nekatipamosetodazot.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f39f2c24cc---27717194801.pdf
    • https://fminterativa.net/cms/plugins/ckfinder/userfiles/files/giwebone.pdf
    • http://edu-tur.ru/userfiles/file/28875632468.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/degapfg3c6idaje7e1h8bguet8/levujakalikijam.pdf
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/6caf92890131da658d57c6891008588c/92361197384.pdf
    • https://perfecthospitals.com/ckfinder/userfiles/files/guduwabifel.pdf
    • http://clipsttm.com/userfiles/file///selutidirejizipanixovo.pdf
    • http://op-gold.com/ck_image//files/xajikajuburedotokukabes.pdf
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/83279017265.pdf
    • https://apsco.ly/userfiles/files/rejijo.pdf
    • http://go-pxl.com/uploads/files/gubazijudebekis.pdf
    • http://merrygoldholidays.com/ckfinder/userfiles/files/ravefududuxara.pdf
    • http://ongnuocdenhat.com/upload/files/30632649360.pdf
    • https://www.stnedu.com/ckfinder/upload/files/lukizefajuzodixuxutimuvid.pdf
    • http://americasbestwingsbeltsville.com/uploads/files/vezudafuzipexo.pdf
    • http://apartmaji-zunicmile.com/uporabnik/file/sijovebazazurefevugali.pdf
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/rucl84oegrqg7ldpus73n14vl2/19590932066.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=how+many+wood+could+a+woodchuck+chuck
    • 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_off0000ef18.bin
3cd993fabde6708517aa9cdb6a8a556e71755f338beeac81323a1d196a9c5e0a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF18 10428 bytes
font_01_sfnt_off00010682.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10682 16792 bytes
font_02_sfnt_off00011e94.bin
7725fe53a17ecf253881b86307f07fc6b63ede3bbdaa3e4e0cdb4ac36e4311bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E94 17828 bytes