Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb73632fd4bc378b…

MALICIOUS

PDF

150.0 KB Created: 2021-09-03 23:58:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6ae496940a80e22792245fbbacf7e6c6 SHA-1: c54e217fe2b82b57ae2fff100322c9d585a3e9bf SHA-256: cb73632fd4bc378b4cd33d8448e695209bc9a89fcca54466f13eaf3817c9ce9b
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. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics further supports this, indicating the document's primary function is to facilitate access to external, potentially harmful, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://pixomot.ru/uplcv?utm_term=weaving+it+together+1+third+edition+pdf PDF link annotation
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b4491b2474---josisesawajaxowolejo.pdfIn PDF document text
    • http://bundoreh.com/fckeditor/files/file/xuvajazuligikaposi.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/48973519028.pdfIn PDF document text
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/7krla4u7dcc9kop9cqr04ofqa4/4074066634.pdfIn PDF document text
    • http://integrotech.com/zdjecia/file/nalalanegebav.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/aadta8mkfincgm1475ouj33cn0/bogekunimigedevaw.pdfIn PDF document text
    • http://banphimchuot.com/userfiles/file/mizujosaje.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/87545959593.pdfIn PDF document text
    • https://mr-alian.com/upload/ckfinder/files/rulejuxag.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-8-10/20210810105556654853.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/0397bf289221195eabdd400915e9f38c/porikezamitiwuvolo.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/rh1hub5t5cs2smd37d8a8k4kn6/zudunegawifujebipoxodowol.pdfIn PDF document text
    • http://congtyvima.com/images/Download/darisef.pdfIn PDF document text
    • http://zhjpharm.com/upload/files/mudazitapuxuseremobebopit.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/8d42c22480a48bfdd3e88dd846f03012/82934322869.pdfIn PDF document text
    • https://jewfri.kr/files/image/files/9559129702.pdfIn PDF document text
    • http://edanieltour.com/FileData/ckfinder/files/20210724_B948B5BDC1AAFCB5.pdfIn PDF document text
    • https://groupunsur3.com/contents//files/60697108066.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/7263152741.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607cee7ff33f5---67719040602.pdfIn PDF document text
    • http://energy-labels.com/userfiles/file/41362673851.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160acc30c6e29b---35828619538.pdfIn PDF document text
    • http://myconnect-thailand.com/image/upload/File/95803525702.pdfIn PDF document text
    • http://3dsami.org/uploadfilefiles/baxovij.pdfIn PDF document text
    • 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_off0001e41a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1E41A 20424 bytes
SHA-256: cc0e9f82af4117167534cb68cffb0da29222bf0712c205ca60ecd6d19b16415b
font_01_sfnt_off000219c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x219C6 10672 bytes
SHA-256: f158e33ad2e3834a76d6ded6f45c6db214253a4ad9006029d64e2e6c806bd2d0
font_02_sfnt_off00023202.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x23202 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1