Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c44ff8617c2639f…

MALICIOUS

PDF

70.1 KB Created: 2021-09-25 12:21:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e55d0873bb6b471526e7ca6b0840f8ee SHA-1: 19dcf4a7e3c5e41d2e5beae878e9b6e9cdfd7c92 SHA-256: 3c44ff8617c2639f49ad45e6152c6ba8b2c37c72aa6677563dd20a00945b1512
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, identified by the PDF_JS heuristic, which is a common technique for delivering malicious payloads. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely downloads and executes a second-stage payload from one of the numerous external URLs found within the document, which is characteristic of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://mosallaesf.ir/uploads/ck/files/10099133294.pdf In PDF document text
    • http://e-sportis.com/images/upload/gotawejatu.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/161410f2447e29---67623432566.pdfIn PDF document text
    • http://kbautotech.com/board/datafiles/imagefile/rifodurobonatopisogojo.pdfIn PDF document text
    • http://oodow.cn/upload/file/210912152315895402gp6x3bwabjs5.pdfIn PDF document text
    • http://fukaofoods.tw/uploads/files/202109210620116487.pdfIn PDF document text
    • http://offerseir.com/basefile/offerseircom/files/52296514623.pdfIn PDF document text
    • https://szallas-karpatalja.net/upload/wimawunifetavenetex.pdfIn PDF document text
    • https://mtestbd.com/assets/uploads/files/xopebotefaxefoju.pdfIn PDF document text
    • https://cobaltinc.org/userfiles/file/33517078080.pdfIn PDF document text
    • http://elmbbq.com/uploads/files/72574763732.pdfIn PDF document text
    • https://foodvellythailand.com/upload/files/fubidimiwa.pdfIn PDF document text
    • http://dotykbylinky.sk/_subory/subory/80478359438.pdfIn PDF document text
    • http://xn--12cm8caae5d9a0a0a1dxk6dd.com/user_img/files/95496348629.pdfIn PDF document text
    • http://red-persimmons.com/upfiles/editor/files/3552364630.pdfIn PDF document text
    • http://intproplaw.com/admin/uploads/file/75618633516.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613078c15558d---zarajinijapafawoga.pdfIn PDF document text
    • https://tanvietnamdinh.com/uploads/files/notilon.pdfIn PDF document text
    • http://cosonhuath.com/hinhanh_fckeditor/file/53923038761.pdfIn PDF document text
    • http://gunjanjain.com/app/webroot/js/uploads/files/temovoxizotebabun.pdfIn PDF document text
    • http://wonikquartz.com/upload/editor/file/1631917017.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/gufufipodekuvuwix.pdfIn PDF document text
    • http://phoiinnhiet.com/images/uploads/files/13878984300.pdfIn PDF document text
    • http://shop-exclusive.cz/userfiles/file/rexanafo.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/data/editor/file/gegola.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=first+android+with+fingerprint+scannerPDF link annotation
    • 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_off0000b300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB300 15064 bytes
SHA-256: 13bf9d26ce6236f1debaa383649f618c2864fdc2cdba083f64d59e6c35232dfa
font_01_sfnt_off0000d91f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD91F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f136.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF136 10916 bytes
SHA-256: 38e13140f396393b7e6d30995be90f8d42c193b46b246f30add5d851d2873530