Malicious PDF — malware analysis report

Static analysis result for SHA-256 63aed381c32fe478…

MALICIOUS

PDF

68.6 KB Created: 2021-10-04 10:15:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3324a63f4ed487e585c7def624bfc9bc SHA-1: b70ef5af6b7166b0d5d72591ed00a44a1621604e SHA-256: 63aed381c32fe4789e6a5445aa63df3979137e29fc2a2e5e5b8372c9fb3e366e
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to PDF files hosted on various websites, some of which appear to be compromised CMS uploads. This pattern suggests an attempt to manipulate search engine rankings or distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://noahmission.org/dataroom/file/19297302864.pdf In PDF document text
    • http://rbc-bezorgdiensten.nl/upload/surukufatebotiregomevaki.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1612fbdc31829d---tezatatesetuz.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/jopujisipobopugawozibo.pdfIn PDF document text
    • http://0225674989.kad.tw/kads/ckfinder/userfiles/files/vebes.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/t3aieqcdaek7441nvaduptbit1/98182345589.pdfIn PDF document text
    • http://astprom.ru/sites/default/files/file/zaromokitulomo.pdfIn PDF document text
    • http://kirakuramenandsushi.com/uploads/files/1959720372.pdfIn PDF document text
    • https://y3stwk65l-mn9.com/contents/files/38029049420.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/cf05648a3768f1110f6af630290a8895/21144107659.pdfIn PDF document text
    • http://yao-cheng.com/uploadfiles/20210924095340.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/16457627001.pdfIn PDF document text
    • http://eastcity.hu/ufiles/file/rewedisojidozi.pdfIn PDF document text
    • https://www.icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/vulivo.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161379dca873f2---watufewuzusatu.pdfIn PDF document text
    • http://www.ville-dammarie.com/ckfinder/userfiles/files/58675539894.pdfIn PDF document text
    • http://cathugo-catamarans.de/res/wysiwyg/file/80048890515.pdfIn PDF document text
    • http://www.uc-kushiro.net/images/library/File/rajoxilavurufowulajasi.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/63324464140.pdfIn PDF document text
    • http://studiomilano.eu/userfiles/files/85869933657.pdfIn PDF document text
    • http://bhartiyambeohari.in/userfiles/file/63795309988.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613267fcd98f7---mitifu.pdfIn PDF document text
    • http://gianenricofabro.com/userfiles/files/fexerulaxabigakemisow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=annual+weather+in+charlotte+ncPDF 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_off0000af1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF1A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC731 10324 bytes
SHA-256: b25b3ce1c5808ca97330f1f041d64f305d03cf6c5f0e1ac566471d61311b8bb3
font_02_sfnt_off0000de7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE7E 15160 bytes
SHA-256: 3f793c815a24473005b0c4c8df541b67c76cb5e297fa42ab81a942d60e830421