Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9cabc885ad5525d…

MALICIOUS

PDF

88.6 KB Created: 2021-08-25 04:53:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7eed05693024bfd90afeb8ee8c1be71b SHA-1: 15253299b0071cd505c3e8091395f848a328f36c SHA-256: b9cabc885ad5525d811939342acf32f5fe4dcdc0172706991226533735507d1e
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The presence of link farms on potentially disposable hosting further supports a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d3ea11023ff---wazitaweguliro.pdf In PDF document text
    • https://piuspvc.it/userfiles/file/83019856580.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607ecd32b7697---42864341972.pdfIn PDF document text
    • https://tuoitre.bacgiang.gov.vn/lib/ckfinder/files/nutopuzis.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16073c1c3adf1e---26979368691.pdfIn PDF document text
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/72fa1cee3a18db77ef897128327fa8bf/kexumulavekado.pdfIn PDF document text
    • https://pubs-icfas.org/icfas_new/dev/ckfinder/userfiles/files/64208579930.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/nefijunel.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/7avnq3nvia8so1qekui896hs22/9046942768.pdfIn PDF document text
    • http://ekhoron21.mn/uploads/files/ponuxulokef.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/9c5bc697fe75f261b0b11e5b34f79ce4/sanejowelatimixiwekibune.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096addd688e2---42342336009.pdfIn PDF document text
    • https://edcasys.com/ci/userfiles/files/68609285702.pdfIn PDF document text
    • http://obasekiestates.com/UserFiles/file/juwuruwozagikexazaru.pdfIn PDF document text
    • https://bold-iot.com/uploads//files/202108021812549778.pdfIn PDF document text
    • http://florylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zerepegugusizadogexi.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/fc54c1f7cd8390b7e1921b85fbe8ca5d/43631351773.pdfIn PDF document text
    • https://inverpalmas.com/aym_image/files/7737288245.pdfIn PDF document text
    • http://flirdining.com/uploads/files/47376492388.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/344d7df49f73438e54483848c5c4676b/60765469769.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/90e6aa8e824bbd9a18dd7b0e6fa110a7/31694571650.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160f0e4b230b0d---75245881682.pdfIn PDF document text
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/ag03hdp6or1h4p46p804p2a4f5/jimek.pdfIn PDF document text
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/nuwasudusilesekogelevad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=api+testing+interview+questions+and+answers+for+experiencedPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4E4 16980 bytes
SHA-256: 0c20513877822881ff249f4d3f296c8869f75a235422a5fdd64d4371abf41fd4
font_01_sfnt_off0001209a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1209A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000138b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138B1 11228 bytes
SHA-256: 3a1439b0f57575429657f42b20202a5a1353d6dcc32afa9ddb6e843ea1224055