Malicious PDF — malware analysis report

Static analysis result for SHA-256 3774879a88567850…

MALICIOUS

PDF

71.3 KB Created: 2021-09-12 19:09:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0fa09cd0466ee3a48265729eec739093 SHA-1: 08c7c0f42820ccc9cd40f91b0033d2ddcccb4ef5 SHA-256: 3774879a88567850056410a97abd0895c6872796627effea48b3516fc6e7b0c3
164 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's part of a phishing or malware distribution scheme. The presence of a 'download button' lure further supports this, aiming to trick users into downloading a payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://dnm.tw/uploads/files/202109101519197666.pdf
    • http://poexali.org/static/image/_u/system/files/49074164815.pdf
    • https://sabresources.com/FCKuploads/file/sawojazipibojijibate.pdf
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc1dc6e4e2---38032166302.pdf
    • http://k9careclinic.in/ckeditor/ckfinder/userfiles/files/79458942710.pdf
    • https://tutorlookup.com/ckeditor/ckfinder/userfiles/files/givuxuvol.pdf
    • http://www.hgbehringer.de/img/files/files/29010614335.pdf
    • http://husplaza.hu/editor_up/wowinipexuse.pdf
    • http://domusanna.it/userfiles/files/31867420308.pdf
    • http://gps-tw.com/CKEdit/upload/files/gagabe.pdf
    • http://yevres.fr/ckfinder/userfiles/files/79867487409.pdf
    • http://caydinhlang.net/userfiles/image/file/16278367947.pdf
    • https://www.db-ynox.fr/ckfinder/userfiles/files/780963927.pdf
    • http://familiehollander.nl/images/uploadedimages/file/68370564614.pdf
    • https://pvesc.vn/uploaded/file/3800643902.pdf
    • http://asztalosweb.hu/userfiles/file/pegokenuvareseku.pdf
    • https://ginniglobal.com/uploads/file/60790870449.pdf
    • http://centrlita.ru/archive/image/file/soxowexamofamefobelenus.pdf
    • http://firewheels.pe/userfiles/file/17110456698.pdf
    • https://wheelmartthailand.com/image/upload/File/94401266330.pdf
    • https://ciar.vn/uploads/image/files/zixabikagifidag.pdf
    • http://www.hzkontejnery.cz/ckfinder/userfiles/files/zuwur.pdf
    • https://suavitinhtannha.net/upload/files/tupibovakokogudijunisedi.pdf
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dda23a6ecb---78421807240.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132254843329---78628960680.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=dunsin+oyekan+songs
    • 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_off0000b62f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB62F 16792 bytes
font_01_sfnt_off0000ce46.bin
ba736a44d351f6443f5a670c96c00c287fe12d2d595ba9fbcc543ff70c7a22ef
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE46 10344 bytes
font_02_sfnt_off0000e5ce.bin
c25d0e8434d8755c544995c98d183d24763095b61d6c0c2df6d3b0957e18f452
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5CE 16508 bytes