Malicious PDF — malware analysis report

Static analysis result for SHA-256 140c250e960b20e4…

MALICIOUS

PDF

75.3 KB Created: 2021-09-20 01:30:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7aec54e547f2d549caa717da1168052f SHA-1: 062f06b15b43af89c4b56eca083ad0467e960efa SHA-256: 140c250e960b20e46a3367ab54a48ff7c996340f3f39ce0bb6282c2f65a526aa
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to potentially compromised websites or disposable hosting, indicative of a link farm. ClamAV and ML classifiers flagged this PDF as malicious, specifically as a phishing or trojan threat. The presence of numerous links suggests an attempt to lure users to malicious sites for phishing or malware download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://xn--b8qxb801j.tw/upload/files/65224709206.pdf
    • http://apart1day.ru/file/goxudulidavufekawu.pdf
    • http://nuraski.pl/wsg/userfiles/robegaxiriweza.pdf
    • https://ibexquimica.com.br/ckfinder/userfiles/files/66029379047.pdf
    • https://www.ewdel.cz/ckfinder/userfiles/files/kumevodekazexejapadexu.pdf
    • https://ostrichtours.com/ckfinder/userfiles/files/61350541480.pdf
    • https://weilaimachinery.com/userfiles/files/80883484889.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136397951ee4---82759683413.pdf
    • https://baohohoanglong.com/userfiles/file/ramumafen.pdf
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/d5807320c79273a00e239c6edd561a24/lubukafukaduzibupobogelin.pdf
    • http://karate-talence.com/newsite/userfiles/files/11628043274.pdf
    • http://franzoesischebulldoggen.eu/userfiles/file/winigologasatirepexoli.pdf
    • http://chunmianxian.com/upfolder/e/files/20210920062306.pdf
    • http://traslochimontalto.it/userfiles/files/68328632717.pdf
    • http://glassick.com/userfiles/file/81516678781.pdf
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/bthe1ph4bssksobakgmc2d2olh/lokomagenunozegakuzigajet.pdf
    • http://goldnumber.info/userfiles/file/19994131123.pdf
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/96537221824.pdf
    • https://pragatitic.org/ckfinder/userfiles/files/75439163885.pdf
    • https://onlinendttraining.com/files/46464944559.pdf
    • http://gachbinhduong.com/upload/file/96467105030.pdf
    • http://cserepakcio.hu/xdata/file/73714093850.pdf
    • https://xtrafitcoaching.com/www/images/files/12444164641.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=otaku+anime+senki+apk+free+download
    • 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_off0000c198.bin
eb6761f372479fe31860d3fcba6b0863b68fd46f845d516f609baa8e6fff1680
pdf-font-stream PDF embedded font (sfnt) at offset 0xC198 10960 bytes
font_01_sfnt_off0000db1e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB1E 16792 bytes
font_02_sfnt_off0000f330.bin
611355c8902169b2d1e46f5e6d15ad25a075bc3fdb017be1653a1dfec6820c5f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF330 17016 bytes