Malicious PDF — malware analysis report

Static analysis result for SHA-256 c624958edcccf222…

MALICIOUS

PDF

84.1 KB Created: 2021-09-10 12:44:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 97e5a78b108299eb637faff5ab57d965 SHA-1: 4452b255a6393c278a6c6f6d4ee6ab812329b08d SHA-256: c624958edcccf2220e0c5a5ab309cdf57591c4776718089855a3b19fd3bc112b
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high probability of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to external sites, some hosted on compromised CMS uploads or disposable domains. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings strongly suggests the document is designed to lure users to potentially malicious websites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://allytemp.ru/uplcv?utm_term=which+colors+make+purple PDF link annotation
    • https://qnzar.com/files/mijumu.pdfIn PDF document text
    • http://rooptex.com/uploads/26638522391.pdfIn PDF document text
    • http://yeosingol.com/FileData/ckfinder/files/20210910_70E6F7664AAC2E2D.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/4e7af96c5fcc4183debb7752c63c2c5b/67377670410.pdfIn PDF document text
    • https://tourgardan.com/basefile/tourgardancom/files/62632281942.pdfIn PDF document text
    • https://xedulichhaiphong.vn/images/news/files/492666269.pdfIn PDF document text
    • http://0575zl.com/userfiles/file/93915845838.pdfIn PDF document text
    • http://tarnava.eu/user_images/file/15621405647.pdfIn PDF document text
    • http://ecme.site/2015/vat/upload/files/lakowal.pdfIn PDF document text
    • http://malovanesklomh.cz/images/file/32573165064.pdfIn PDF document text
    • https://newcar-rental.com/uploads/files/202109051525455391.pdfIn PDF document text
    • http://lotusburbank.com/uploads/files/12296944934.pdfIn PDF document text
    • http://polins.org/public/userfiles/file/kedigiwometuwibop.pdfIn PDF document text
    • http://embody.box8websites.com/ckfinder/userfiles/files/movapiwovonofiv.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161361bd6b856c---vabep.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138c0b5c6732---40780228371.pdfIn PDF document text
    • https://bahamianbrewery.com/ckfinder/userfiles/files/sefenoditunigukigo.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/99207550365.pdfIn PDF document text
    • https://louvre.lv/res/wysiwyg/file/kopaxulolugafatigi.pdfIn PDF document text
    • http://easternhoteljeju.com/FileData/ckfinder/files/20210907_33AD2E6E7946240E.pdfIn PDF document text
    • http://bulongvungtau.com/media/ftp/file/jevabokupuwepulatanaweg.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_off0000e613.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE613 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE2A 10624 bytes
SHA-256: ee787a04ea634dde1f672f1574116fea83e5c77646ac246a113270779571ef1d
font_02_sfnt_off00011674.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11674 17748 bytes
SHA-256: 36a6fddf048c5aec32af4c37b8327043e193d3241e0847b391671766603a7c4e