Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e55bc881551b1ca…

MALICIOUS

PDF

93.0 KB Created: 2021-06-26 15:45:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7447d71c2c8d121b888dd7c7af1f86c9 SHA-1: 588c8f8caf89c814acc493d5bab4385f1ad4617d SHA-256: 4e55bc881551b1ca22656d725370ae907e7efebfc5ed3ba2a43f4cdd3f68dd8e
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links to compromised websites, indicating a likely phishing or malware distribution scheme. The presence of multiple links on disposable hosting and compromised CMS uploads suggests an attempt to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ccfce59edab---96363514212.pdf
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/7b3a8e41d848ebd9c8153d555e033f51/nepopufisilenoxobizugise.pdf
    • http://short-story.ru/upload/file/wiruturedoki.pdf
    • http://veivel.com/userfiles/file/96076383140.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c970142b899---13268106841.pdf
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608230cfd968f---wisozotixemelonupogof.pdf
    • https://ctsgroups.asia/images/file/vufaxomoxetojibewumi.pdf
    • https://sport-jicin.cz/dokumenty/fuxotaxo.pdf
    • http://ilovegabal.net/fckeditor/_upload/file/wororob.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160701ee890a20---93157414342.pdf
    • https://ancoraeducacion.com/images/tezumak.pdf
    • http://askort.pl/Upload/file/14221140780.pdf
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/194f06550fd93bb9dac5b99f9f0ecfbd/lumoposunu.pdf
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/pns52pb10ur74bl475nggq2ba3/25293127093.pdf
    • https://turbooto.vn/upload/files/81599286549.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c119f011195---70834446985.pdf
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0ea12473bc---wibumatafudekena.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082bdce76ade---14693293236.pdf
    • http://chukysovin.com/img-svc/files/motatafefonexafixagunomur.pdf
    • http://eltonltd.ru/sites/default/files/uploads/51859265410.pdf
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/jl51qcmhplr453fedqom1im5ab/fikuguvinidar.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=diablo+2+single+player+leveling+guide
    • 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_off000109ea.bin
01a98f8e4905b1ae399249b427d66625c2fe996808e341eea76fb59fc1301a3d
pdf-font-stream PDF embedded font (sfnt) at offset 0x109EA 11008 bytes
font_01_sfnt_off00012340.bin
b8b0b0327149837ba98dbcece17c6834bb25240d1bbdeaa3938be122f4fcfd9f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12340 16784 bytes
font_02_sfnt_off00014efb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14EFB 16792 bytes