Malicious PDF — malware analysis report

Static analysis result for SHA-256 503b83f28135002d…

MALICIOUS

PDF

109.0 KB Created: 2021-07-17 12:48:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: b317177758494ed0b476b8c7adf864d1 SHA-1: 945eef49ca6d92c17139d26811a7fddc87424a66 SHA-256: 503b83f28135002dfb46dd814ce7645d4c05d2be215c427e06089dfde2397b3a
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm hosted on compromised WordPress sites, with multiple URLs pointing to potentially malicious content. The presence of these links suggests an attempt to lure users to external malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9756

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://ajwatravel.com/wheelmarine/userfiles/file/piragipurilariza.pdf In PDF document text
    • https://chaletsuenodesol.de/files/23733045827.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/rededutuzosesitidawusuwek.pdfIn PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/pazobuxudadewirel.pdfIn PDF document text
    • http://xn--b3ct0dc9bc4a4g.com/userfiles/files/rilevuxefipasewel.pdfIn PDF document text
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c2a4414b68---28898041748.pdfIn PDF document text
    • https://iamtimeshare.com/userfiles/file/31788802176.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1609db7118d0ab---sesuwuwisavujawuzifele.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094df16a58bc---kosekunujojude.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7bf84d745---16944117820.pdfIn PDF document text
    • http://skyline64reunion.com/clients/e/ec/ec378541aa9b73e2b99de5ca5545ec21/File/nadevijatibaxe.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607133f56c637---25377257837.pdfIn PDF document text
    • http://zap-interactive.com/uploads/files/19453952345.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/272b333d117a04212a356ee5c4993ce9/zubatibufesafari.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b28dd1ed2c---25990490679.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/zixilufeker.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/317ee27a4dbe6ee9e846433a866f6139/jowezegonobagogesirelalap.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/55754242490.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/u0sa3o0vvjm03nq50g0o11blm1/wipegedi.pdfIn PDF document text
    • https://dukra.sk/editor_uploads/files/sowokisepasusafugekam.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16080743609fee---jijotutizozaxovekekaw.pdfIn PDF document text
    • http://tipiland.net/upload/file/85080684487.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608afeb37d0ab---bufekazerinekegodox.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/16075bee31d065---tejuxilevumatolesi.pdfIn PDF document text
    • https://chetanaus.org/bheru/uploadfiles/file/46526597783.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=check+intersection+of+two+linesPDF 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001190e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1190E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13122 9156 bytes
SHA-256: 66ffaa30ddc133192bd6b9b91c3d0a98fec0e835c52c2125407ea0be108e11ad
font_02_sfnt_off00014456.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14456 19160 bytes
SHA-256: 4ef9e3474204a0ded3caacb8c8dddf3fcad4f321d3e7ac265bc1bc12aeafbcf2
font_03_sfnt_off000177c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x177C5 16260 bytes
SHA-256: 12474f496bf448c2c48004622071f5f19fe7b8005b752c22de1498c6765ddbf4
font_04_sfnt_off00018ddf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18DDF 10480 bytes
SHA-256: 37507479f34019a5dab28f46f587aa1af08a25a314dec200ac1d1636e5651d9d