Malicious PDF — malware analysis report

Static analysis result for SHA-256 88fe39fb1d893723…

MALICIOUS

PDF

75.9 KB Created: 2021-06-28 03:41:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2c27815d413b6e6087a5bb760bd6cedc SHA-1: 59f374d069f498f0b768f986c07a98045b1d2e4b SHA-256: 88fe39fb1d8937235841dd7ad5cfb111753456ef0afbe0168eaec34411f73260
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple distinct hosts, many of which are hosted on compromised WordPress sites. The embedded URLs suggest an attempt to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088183e95d2e---35258689298.pdf
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/q7pgtprau5i7gs0m4qkir67d9p/wukafiv.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160945fd7164cd---37341125462.pdf
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f8e49a9559---wamubugakegarofuva.pdf
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/dl3n1fokb4mfi225f762e7e1um/mogigixurap.pdf
    • https://bestcoloringpages.com/userfiles/file/63040303512.pdf
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160948160408b9---momizamikaselisuziwik.pdf
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/c7955c05242d0a7dc34d6e0acbb142ba/84726456364.pdf
    • http://school19-zav.ru/userfiles/file/66556732873.pdf
    • http://allamericannursing.com/userfiles/file/wulaluwoveganesuvarulud.pdf
    • https://yepsell.com/userfiles/files/37277327221.pdf
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1cac137b5---21365275870.pdf
    • http://samurairamenbar.com/uploads/files/xazugabimonujiwiwefewok.pdf
    • http://ebiocell.com/uploadfile/file///2021052513000439.pdf
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/c86a92a2fc031941da04a3c3bd261d8d/64484878473.pdf
    • http://cnzgks.com/userfiles/file///6937178795.pdf
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d079857d927---27810819236.pdf
    • http://www.firengo.com/userfiles/files/95538553783.pdf
    • http://alumcity.ru/userfiles/file/51373885774.pdf
    • http://eurogeographyjournal.eu/admin/fckfiles/file/34543414570.pdf
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/7lj2g44i4tfnp53vuaeb2oht2b/40217138443.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608434b54fda5---buget.pdf
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0e685397f---19124231231.pdf
    • http://nowyhotelik.pl/userfiles/file/58030496507.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=liturgy+of+the+day
    • 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_off0000c98c.bin
c527f8bf6c546725501235b422289930b2d50513b45f638f99f6755baf700c6a
pdf-font-stream PDF embedded font (sfnt) at offset 0xC98C 15880 bytes
font_01_sfnt_off0000f289.bin
91dc0aa6bbf9ab3261527352dbf4d475c9764b34be5cc76bfd1b23127ad336bc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF289 10484 bytes
font_02_sfnt_off00010a54.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A54 16792 bytes