Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1078bba67dea481…

MALICIOUS

PDF

77.4 KB Created: 2021-09-09 02:56:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 2d23bf9374053ceb2a5e77d37caaa950 SHA-1: 9cd652e643d39e872a4a266107b788fb2061f8e6 SHA-256: b1078bba67dea481e9cb2272475ea58ab4086fadbdd46d165a075533aabe893c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the nature of the embedded URLs and the heuristic firings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://kowalstwwo.pl/public/cms/images/file/witavidixojo.pdf In PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16138f504f394c---85630493167.pdfIn PDF document text
    • http://chieucoingason.vn/files/93494281014.pdfIn PDF document text
    • http://mayjack.com/upload/files/5481480198.pdfIn PDF document text
    • http://vinhhangvien.com/upload/files/79824281789.pdfIn PDF document text
    • http://villabrown.it/userfiles/files/telugapos.pdfIn PDF document text
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210903_124436.pdfIn PDF document text
    • http://slxiang.com/v15/Upload/file/202196205174115.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/gaxex.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/726c13cf04f676002705f5175b3d865f/nuvizaxaw.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/konadukogudutizaliviz.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/kalemojewelusutisivedilaz.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/5b155507261627a495f2759cc8b06b6f/zowelakujixod.pdfIn PDF document text
    • http://ijfbacknumber.org/editor_up/jupugevinotupaw.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/togesakujilefaxodix.pdfIn PDF document text
    • https://fortworthdental.net/cmsCart/upload/file/vumixenos.pdfIn PDF document text
    • https://macauroommate.com/ckfinder/userfiles/files/talokefod.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613632bf41dbe---6277831710.pdfIn PDF document text
    • http://ancheng-medical.com/uploadfile/files/49520680984.pdfIn PDF document text
    • https://mavachhaiphong.com/upload/files/68365528312.pdfIn PDF document text
    • https://soalmatematik.com/userfiles/file/27739604142.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=call+recording+in+mi+note+9PDF 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_off0000c976.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC976 10744 bytes
SHA-256: f1976dff584b004ae368639cf2c18f10629a6ff34469569c00ee98bbc4753291
font_01_sfnt_off0000e1f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F0 17684 bytes
SHA-256: 9ccd7762d1f3322f0f09a7fef6aa158e0a30fc60d514da037d4e1df68887adda
font_02_sfnt_off00010ff4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1