Malicious PDF — malware analysis report

Static analysis result for SHA-256 912a8c0939dc313c…

MALICIOUS

PDF

77.9 KB Created: 2021-07-03 20:54:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4773c7557eef43b98c3b73fba5c3a856 SHA-1: 82cc779fdc86ea2d521f656773e23d9af8abee69 SHA-256: 912a8c0939dc313c3952344a678614b25493fcf214de2934925ca76f4b0ba872
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a high-severity PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM. The file contains numerous embedded URLs pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to redirect users to malicious sites for phishing or malware delivery. While no scripts were explicitly extracted, the nature of the embedded links and the ML classifier's output strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.pirac.org/wp-content/plugins/super-forms/uploads/php/files/0c1342d5f85424f9774edfd848d3bbff/35792331005.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bfbc6a8bc0d---88646249680.pdf
    • http://immobilieninvestors.eu/userfiles/file/widuxuvuratesig.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/a917c6f954169bd841301cf081530224/litatesoselo.pdf
    • http://driscollandgibson.com/images/edit_images/file/58753755576.pdf
    • http://renovator.cz/files/file/5831945730.pdf
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/36b0fe1c7292d19806a0d7ce0dab5294/32406598166.pdf
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/c03c1abfc7b1275a4d75794c86c8ee18/votakefi.pdf
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/706411ccfac0324d4e00b5c288404d63/37635950021.pdf
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/798cf0f34eaf6d6e055c11db1632504b/kosixenowajepasizejefili.pdf
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160741e2fa14d6---72604691663.pdf
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/da843b79ec8a9f3a30f69fa377e10093/pevitexogalowodumesuwiba.pdf
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/caa7950354e7a1fcf2dc0c5239efb0cc/tajawe.pdf
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/5pe71fositvadtfk4eukmjvrco/motajusakijatiposimesu.pdf
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/r942s6i8ik6opb4kidtsskgm2e/45015205559.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160acc57f5ae94---ramoxomuzapo.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/160875c595ea75---95095691964.pdf
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9453b34d71---54843890940.pdf
    • http://goldenteriyaki.com/uploads/files/44669666762.pdf
    • https://ortechindustries.ca/ci/userfiles/files/24764076867.pdf
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/2252737fc0f2079e713648d3347c3162/korapararagajubomobefu.pdf
    • https://fnb-concepts.com/images/uploads/files/pexanemovubabogufu.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/jvid9si0s9tis2ebuqjd48i3a6/72535091665.pdf
    • http://travelport.pl/userfiles//file/dibirepogumef.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=post+and+pier+foundation+earthquake
    • 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_off0000ccfa.bin
27176df83850197e95b106ef7695d9133319af51eeab382d408fc3538f61f04c
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCFA 10888 bytes
font_01_sfnt_off0000e5ee.bin
d069ad16ae04e64891331abf153b4573b23ac1a1f71b593d2965bb12f3ee1f15
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5EE 16924 bytes
font_02_sfnt_off00011249.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11249 16792 bytes