Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8947856ce9f6650…

MALICIOUS

PDF

71.6 KB Created: 2021-09-28 01:36:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e1008d57c5fb79ae26092a4ad8f195bf SHA-1: f4aa1968d63253afab7e2ee3cbef883b9490715d SHA-256: b8947856ce9f665016a08979ed00e1d125aa7039dbd777519723372161c9dc41
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs, many pointing to compromised CMS upload directories. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple links on disposable hosting and compromised sites suggests a tactic to evade detection and distribute malicious content.

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 http://geraldinekilkelly.ie/28997745563.pdf In PDF document text
    • https://samsungklima.net/upload/ckfinder/files/75933031409.pdfIn PDF document text
    • http://synhbio.com/upload/files/rewiruzemarujusukoluj.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/6c43f14fd1f1db5e653f43956138a507/lanuf.pdfIn PDF document text
    • http://kiemdinhcan.com/Images_upload/files/965166828.pdfIn PDF document text
    • https://mlmrockstars.com/ckfinder/userfiles/files/38008907717.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/5ugbcacfv2f1ipuead0vrabv1u/13620019805.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/salanal.pdfIn PDF document text
    • http://dennehylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/52742781892.pdfIn PDF document text
    • http://zs-oilfieldequip.ru/d/files/sixitibobewedojizeputeb.pdfIn PDF document text
    • https://saint-florentin.charcutier-traiteur.fr/ckfinder/userfiles/files/magiguvajo.pdfIn PDF document text
    • https://studybrilliant.online/app/webroot/img/userfiles/file/runuruxozezokuge.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/2b05418a15b756491ddc73640ffe715a/tiwiluniwesepotilovakem.pdfIn PDF document text
    • https://bakwanudang.com/contents/files/14006238875.pdfIn PDF document text
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/22216687629.pdfIn PDF document text
    • https://uudanbury.life/files/file/94839127883.pdfIn PDF document text
    • http://amicissiapiemonteisa.it/userfiles/files/ruzunuwelopu.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142e4e59d75d---ruvodenoxid.pdfIn PDF document text
    • https://transturist.ba/ckeditor/ckfinder/files/files/guvufom.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/3d87e3074a6bcb8633c81c51c6e2eec1/30067462504.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-9-22/20210922003906550441.pdfIn PDF document text
    • http://godsownproperties.com/userfiles/file/xideletolalulokovewikas.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/zokuvenevag.pdfIn PDF document text
    • http://blackhorsesc.pl/userfiles/file/sugodoradobunitemiv.pdfIn PDF document text
    • https://mimpi1pusat.com/contents/files/98598387623.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=castle+crush+download+mod+apkPDF 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_off0000b52f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB52F 10996 bytes
SHA-256: ad8061d05eab0f160c25413330d5b44a6fdc331c726f6ca9d4d5e6fdad0de028
font_01_sfnt_off0000cea4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEA4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e6b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B6 16480 bytes
SHA-256: 1c5c3f5eeb9b5718cdbb1174c5e60d681e2aff215fd4db0032f0bc61cf4a20d5