Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1606255d893ffe8…

MALICIOUS

PDF

68.3 KB Created: 2021-09-24 15:06:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 41ed197f5ad099e793b18c61ffb26d0f SHA-1: ff09e91bccd5b3cb377d5603e533ac31273dae55 SHA-256: b1606255d893ffe879661ae1070569e1d3e094f4db11b5a3cd0bc30c6848605b
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as a phishing lure due to its image-only nature and the presence of numerous external links, many pointing to compromised CMS uploads or disposable hosting. While no scripts were directly extracted, the PDF structure and link farm indicate an attempt to redirect users to malicious content. The ClamAV detection and ML classifier further support its malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://www.tahitotfalu.hu/ckfinder/userfiles/files/kidovulewitepovofexeloj.pdf
    • https://j26clean.com/upload/files/ronizefowumesom.pdf
    • http://we-women.de/default/files/uploads/file/76923016543.pdf
    • https://pvcmikser.com/upload/files/gosagap.pdf
    • http://zonweringbelgie.eu/ckfinder/userfiles/files/78694674313.pdf
    • https://alummaswaja.com/yii/sdbalikpapan/home/images/upload/files/rogimunitilovola.pdf
    • http://pharmorgsyn.com/upload/files/sidilobefadiru.pdf
    • http://internet-trade.cz/UserFiles/file/foluxadirekekeroxon.pdf
    • http://airfa.it/userfiles/file/24813111466.pdf
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/lujiverarijak.pdf
    • https://escolaalfa.com/userfiles/file/62878409255.pdf
    • https://menlopark.com/wysiwygfiles/file/61838718735.pdf
    • http://koreaticketland.com/userfile/file/guxobuto.pdf
    • https://tatvan.in/userfiles/file/91912022084.pdf
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/37272370294.pdf
    • https://unifor975.ca/userfiles/file/zudepe.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303b94434dd---wegodapejofesejumuzawu.pdf
    • http://gemmacapitalgroup.com/foto/file/bagufibowuxupo.pdf
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/36cf482d7c4d36fc35c356d34bc628ca/pufogufosamaji.pdf
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb0905a419---zodojuve.pdf
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/16131914f0e7ac---tixirazokolavulobikafa.pdf
    • http://locnuocvietmy.com/Images_upload/files/davinedevogojaxajozo.pdf
    • http://planet-for-events.de/userfiles/file/fatose.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=eventbus+android+kotlin+example
    • 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_off0000acfd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xACFD 16792 bytes
font_01_sfnt_off0000c514.bin
596a0afcd3ba20d27066081812975ad0b77efce0097cf132159778327d89e135
pdf-font-stream PDF embedded font (sfnt) at offset 0xC514 11036 bytes
font_02_sfnt_off0000de83.bin
2a8f421a1941535742e395e24315be59c0ca38b0e829cb2d265c1c69aaaac779
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE83 14300 bytes