Malicious PDF — malware analysis report

Static analysis result for SHA-256 41b8f7991e7949bb…

MALICIOUS

PDF

91.5 KB Created: 2021-07-20 18:42:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 5c73c83f4c0b6a5ddc4b9f4207650058 SHA-1: 491d5dd0e3ada5773a11258f10fd92646aa73d2f SHA-256: 41b8f7991e7949bb2cda18335fd748cd42ebbc864e529e424dc82eeefdda687d
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to compromised websites, suggesting a phishing or malware distribution scheme. The PDF structure and embedded links point towards an attempt to redirect users to potentially harmful content hosted on compromised CMS uploads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://whatifitspossible.com/ckfinder/userfiles/files/34338571405.pdf In PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/3266d825af5153166041936785b61682/33549190362.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/048fe34bfc36271f3d06e975b49a362b/wawenamopokeril.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/pb7dvk20cr8pfm20gkrk36dfs5/guluj.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606da3b44798d---54220718322.pdfIn PDF document text
    • http://spc1991.com/ckfinder/userfiles/files/13319481377.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/gupigem.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c37ccf59539---85823488877.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/wobower.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/14252473008.pdfIn PDF document text
    • http://hilltoplancers1975.com/clients/13753/File/65720765714.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160761e34ae29d---42594918402.pdfIn PDF document text
    • http://mobydick-band.de/fckdata/file/jimure.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/160b20b4fb1c33---vogiwazipojavixekokaloje.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/ko6ifpdkrbucrf0e2o0c4fa2oc/53754384962.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160befc4f72f06---33168824054.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=oxford+german+dictionary+pdfPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e85a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE85A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001006b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1006B 16544 bytes
SHA-256: 66b7945b99a9c78025a9a0ace4161995b24b08b80ea391fd428eddc3553bac27
font_02_sfnt_off0001172a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1172A 17716 bytes
SHA-256: 6b2a82616588f8a934633f9f5ef49aca83f3c73c314961461f8e72faea9246f9
font_03_sfnt_off000145a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145A1 10992 bytes
SHA-256: ef1c5261767764fb40daa1f96a36ee65bcb13253b72acac5eeee0de30bc245d3