Malicious PDF — malware analysis report

Static analysis result for SHA-256 a14acfed673c3039…

MALICIOUS

PDF

83.2 KB Created: 2021-09-19 17:44:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 454c7604d8c9b086df874948147e288e SHA-1: 9afa3e22c3d02b742deb1f09a683661739bb3078 SHA-256: a14acfed673c303933a257880daf28fd5bb880334b07aa0f6499dd5e482861a1
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs pointing to various domains, many of which are associated with compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, suggesting it serves primarily as a container for these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://laborke.ru/uplcv?utm_term=oldboy+2003+english+subtitles+watch+online PDF link annotation
    • http://stroyvodservice.ru/upload/File/nujoxejozosulonotomem.pdfIn PDF document text
    • http://mmsmarin.com/imgimage/file/85432083446.pdfIn PDF document text
    • http://marleenjansen.nl/images/uploadfiles/53130926975.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1613102bbcbffd---13893751555.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/b3c06348fca311854fcd9ee790ff7bf1/lijelizu.pdfIn PDF document text
    • http://bn-biz.com/userData/board/file/tumimejaje.pdfIn PDF document text
    • http://hong-tour.com/FileData/ckfinder/files/20210914_7B685B690F55E856.pdfIn PDF document text
    • https://marthomaktrplrdiocese.org/ckfinder/userfiles/files/37526588646.pdfIn PDF document text
    • http://wrtour.com/FileData/ckfinder/files/20210912_C834360C3FB1149F.pdfIn PDF document text
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/53856144380.pdfIn PDF document text
    • http://indago-rovigo.it/userfiles/files/mopodidugo.pdfIn PDF document text
    • http://thibidi.vinadesign.info/uploads/images/files/95357488876.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/nudedidunodajumovuzana.pdfIn PDF document text
    • https://doctornhospital.com/banglanews24/editorsfiles/files/wugomalefek.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/8554ce1a3ea937639a14bd4f31fcb1cf/puvaliber.pdfIn PDF document text
    • https://tigaintan.com/contents/files/jemigis.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/91038330144.pdfIn PDF document text
    • http://yomamasushitogo.com/uploads/files/2262362954.pdfIn PDF document text
    • https://bestcaps99.com/ckfinder/userfiles/files/89361139444.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137eae98130a---47983951539.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_off0000d374.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD374 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB86 21956 bytes
SHA-256: 37ffd147d53c6561ddb59141c50c685e3916587493b112112fa9bdfdf2ef1989
font_02_sfnt_off0001244a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1244A 11428 bytes
SHA-256: b7c15e461ccfa34f8241c9c8d90850166a85c570ce46dd47a09b572467d315af