Malicious PDF — malware analysis report

Static analysis result for SHA-256 b91c4f88587695ab…

MALICIOUS

PDF

211.3 KB Created: 2021-08-17 12:01:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 121eb7420bc2d5f7559d65215c06b500 SHA-1: 426560010bc4c0a4990031292bcf5510df0a6c14 SHA-256: b91c4f88587695abd441dc513567b203596b976c5a8ff34c9e0bc3aa743f3a02
142 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is a common technique for executing malicious actions within PDFs. The JavaScript likely redirects the user to external URLs, some of which are hosted on compromised CMS uploads, indicating an attempt to distribute further malicious content or phish for credentials. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9926

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • JavaScript action low 1 related finding PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://aprilboya.com/userfiles/file/75861894276.pdf In PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c48f7eccf7f---65946077298.pdfIn PDF document text
    • http://fundacjaproartis.pl/javascript/ckfinder/userfiles/files/vukigakupin.pdfIn PDF document text
    • http://beiks.info/public/file/vonokesisexarun.pdfIn PDF document text
    • http://yetisirkaucuk.com/firma/files/jitafigewidurazikogiwov.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16086b302d85df---92718654240.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/lavuwumakuravobinev.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072679812973---liropibumuraja.pdfIn PDF document text
    • http://tamphuhiep.com/Images_upload/files/43962010609.pdfIn PDF document text
    • http://landonintergroup.com/ckfinder/userfiles/files/32068523694.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-8-15/20210815092713533431.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/ef614b39a6437c6c4eee8be74a6bb22b/lonix.pdfIn PDF document text
    • https://emauto.lv/index/images/up/file/kamif.pdfIn PDF document text
    • https://mm-podium.ro/userfiles/file/30140845593.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16105524a11113---xulebekedarazajupuseru.pdfIn PDF document text
    • http://icloudcleaners.com/uploads/account/autoresponderfiles/75510772246.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/3csum2cl93ml3rdsr1k6vvi350/78328542804.pdfIn PDF document text
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/xivogiwovorumogevurev.pdfIn PDF document text
    • http://innova-perila.ru/upload/files/20836430911.pdfIn PDF document text
    • http://hokeypokeychallenge.com/clients/7/77/77ac66e313b6cb4bf602f1678accca72/File/44557420339.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c22d9ec1525---noziragorifalawesat.pdfIn PDF document text
    • http://regalmotors-jp.com/js/upload/files/togulonizubu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=ode+to+family+photographs+poem+answersPDF 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_off0002db21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2DB21 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0002f333.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2F333 19356 bytes
SHA-256: 625cf78bdacccc3e5d9d5294dfef6b9d0c2930169f515d6bd889d0a8c743dabe
font_02_sfnt_off0003254d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3254D 11172 bytes
SHA-256: 6178d364310a98c1f4a6552c74bb80f155696f2d6b64738a9df123e01918a43e