Malicious PDF — malware analysis report

Static analysis result for SHA-256 90cf2c4fc521b4ce…

MALICIOUS

PDF

92.3 KB Created: 2021-08-08 17:42:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3972929af8d84208bcf82f3e9838d1e0 SHA-1: 1a06a45952614516e1747c33dc8059185860a244 SHA-256: 90cf2c4fc521b4cee884803db8f443be16084600486dbd834d58f931d27929aa
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. The document body is unreadable due to encoding issues, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8473

Heuristics 5

  • 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
  • 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://newgatedesign.com/Images_upload/files/82022048522.pdf In PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/6aff647013d72ae0ee164bef0257941a/norajivodezizojuxef.pdfIn PDF document text
    • http://starlightcelebre.ca/clients/4/43/43e9139217482d7666ce300faf566241/File/ramokadonedut.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160bfe6692bd93---ragovupepanowokubar.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b02467a2eb5---91165359506.pdfIn PDF document text
    • http://www.gpe-el.pro/ckfinder/userfiles/files/seketosuzonopokidovopiju.pdfIn PDF document text
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608b2ab743bda---xulejaguga.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/9q13oa94b0pn2i622vnhq1vq3q/kurevonumezexiwojox.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160bd506778f48---14491331905.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/75ec038c2ccd1aeb8747a8a91ca66513/77189707303.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/ruk2oac0cfrcd1anjk4ojvkj13/vuxenif.pdfIn PDF document text
    • http://brcassociati.com/userfiles/files/12630194501.pdfIn PDF document text
    • https://www.tratedu.net/ssss2018/assets/143ad273/ckfinder/core/connector/php/upload/userfiles/files/0f20750d9accc07f6f7412b6e1b04b6c.pdfIn PDF document text
    • http://udelimpa.es/ckfinder/userfiles/files/komezokenegalimifizo.pdfIn PDF document text
    • http://robertoantoniz.com/resources/original/file/58026482195.pdfIn PDF document text
    • http://vietsonplastic.com/uploads/userfiles/file/fudifejafo.pdfIn PDF document text
    • http://axwelindia.com/uploads/31260548983.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/3fa1130b19f893591fb8e9b6d042e14b/witofid.pdfIn PDF document text
    • https://fairtradeportal.pl/userfiles/file/83951497497.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/46059368058.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608d85c678090---wuzegado.pdfIn PDF document text
    • http://kinel-hunter.ru/upfiles/file/30323200088.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/adpr7cfjo098n186mh6dsl9vc6/lofegitulufemanadibaf.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160893cf392310---norusiruxodelajodopixedab.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/1835c7cccffa4f8598805ed97b78077e/gefidejejoliwalutiwunibuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+pick+winning+scratch+tickets+ontarioPDF link annotation
    • 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_off00010ce0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE0 17880 bytes
SHA-256: 7fad11b055bd100b8d3e14abf09e9eda1344dddadef37a884eff951277f8b4d9
font_01_sfnt_off00013b9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000153b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153B2 10776 bytes
SHA-256: 4e3b5ac1802343fcf4a2182a43896f3eb6031b7cafa94ccc25936eec1caa6bec