Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4e8738e14420959…

MALICIOUS

PDF

78.5 KB Created: 2021-06-29 15:41:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fe575ad7d858c0846f35a020e82c74d7 SHA-1: 148f2c5e00ee0688112ad43b3975b31eb10e875a SHA-256: c4e8738e14420959c0edfb226f002b04f105d3fe947c50864bbee3cc7258ce0a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting it's designed to redirect users to malicious sites. Although no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://coretry.ru/uplcv?utm_term=how+to+write+logarithmic+equations+in+exponential+form
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/3c9ac1250c1fa39838909902b36e5077/24724647942.pdf
    • http://zulassungsservice4you.de/bilder/file/98541487741.pdf
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/88a70f9780a28290840c182d1e417901/86421242935.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d247c937685---13087596754.pdf
    • https://mymango.ru/wp-content/plugins/super-forms/uploads/php/files/608671f136c4e4686bb85c87f98b74f7/nurijulilibabeguzokup.pdf
    • http://vizcsap.hu/files/file/82087844459.pdf
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/090272773d286da456216f3147982987/89540889258.pdf
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/n72ugnrctrobdellbbbb6u6edp/tenogupedisasif.pdf
    • https://advantagelic.com/singhania/downloads/file/81583351413.pdf
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/97df32237b02838fa8c76fa4f231c379/71559716409.pdf
    • http://aep-tc.com/cache/fck_files/file/75255725903.pdf
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160b32cba3ed99---40661343876.pdf
    • https://businessservicesuk.com/userfiles/file/xebeguwuwaf.pdf
    • http://www.derbysignandgraphics.com/uploads/file/vumedobudilanoxamizolopi.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/948ffbf038cb8731b11d0447e49e4ea1/39810551930.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/16079c8669008e---9370003037.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/32lra5v00fc6t621pp0338es62/zegugenurad.pdf
    • http://www.psoealora.es/ckfinder/userfiles/files/9413827425.pdf
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160c8fa48afd9f---jilejeked.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/gjcs93j7aoacvguturpm6sg52h/67181621114.pdf
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9e104a8153---66637411506.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/c16778af340d0892f4f0cce448f2b4a8/lejolotebiruxosaluna.pdf
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/ff42e12da307ab4b353ba44a523f0a0c/zabinowamav.pdf
    • http://ahcxdq.com/uploads/file/071419273153.pdf
    • 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_off0000cb6b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB6B 16792 bytes
font_01_sfnt_off0000e382.bin
62ccd6823dacb49f6fb7486c9ed292c9b9534e72cd19e8751d5884f49824db17
pdf-font-stream PDF embedded font (sfnt) at offset 0xE382 11352 bytes
font_02_sfnt_off0000fdc4.bin
1b496da11cf415e3b56523ff03f0551f91d5f8807b3a79a8d254a4f05a25f6a0
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDC4 17104 bytes