Malicious PDF — malware analysis report

Static analysis result for SHA-256 88fb7438eee013e7…

MALICIOUS

PDF

73.9 KB Created: 2021-09-07 16:44:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a3c4a97ab917a70ec79eb4e3a0dc3e1e SHA-1: 47994527c743431782580bfd748202bc95da54ad SHA-256: 88fb7438eee013e7f5bc591a5df64f14cb1f67442746875c4eaf4ef260c72807
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised CMS upload directories, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a phishing or credential harvesting scheme, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://dulichgiahy.com/upload/file/88229503853.pdf In PDF document text
    • http://vinacafe-dalat.com/Images_upload/files/97018565234.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160982ba96f57d---39962489916.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089f3b144d13---36897441194.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/a57a0ebc374141e1e9ec855d4cb156d2/mezedepafedifimewozu.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/6bshclfuh137u0p2kqdi4erl4p/kuduv.pdfIn PDF document text
    • https://fitness-sport.it/userfiles/file/jubejuzodarel.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/pemereligodepetazukimagi.pdfIn PDF document text
    • https://eurouniversal.eu/ckfinder/userfiles/files/nekigenomididuj.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608ae2efb6e80---mazofowowerivitomadeg.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070c60d6805f---barokugexawug.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/66670115090.pdfIn PDF document text
    • http://winteringlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/7413970229.pdfIn PDF document text
    • http://beepost.vn/upload/userfiles/files/26464034532.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/vfg6ut7rtjqh8i21ij4b2q53mb/xeganulajam.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/28050287672.pdfIn PDF document text
    • https://avgdesign.com/userfiles/file/89778545852.pdfIn PDF document text
    • https://on-call-anatomist.org/ckfinder/userfiles/files/dozewexoponudojikutajofu.pdfIn PDF document text
    • http://stitesattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gogowop.pdfIn PDF document text
    • http://guides2alpes.org/uploads/file/18468440514.pdfIn PDF document text
    • http://xahscw.com/userfiles/file/64970295942.pdfIn PDF document text
    • http://zhansq.cn/upload/file/mipimopigazak.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/9641390012.pdfIn PDF document text
    • http://coytex.net//ckfinder/userfiles/files/45322773570.pdfIn PDF document text
    • https://treasurehunterdetectors.com/ckfinder/userfiles/files/fimuxukenesulolef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=metrel+mi+3125b+manualPDF 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_off0000be54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE54 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d666.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD666 16716 bytes
SHA-256: 37a368f453cb10aa3a70e369c0fba9aa422cb56aadbe2ecad0002800c74abe74
font_02_sfnt_off000101f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101F0 10692 bytes
SHA-256: c67753dd48819901a8730a0976d7b5cf37aa65d288e2938a63a73aea30a800db