Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae8b12584dbb052f…

MALICIOUS

PDF

81.3 KB Created: 2021-09-22 10:04:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 825b5bf0f316540cda1b1d9447e7e01b SHA-1: 03ff3217d92ada7c95b96a60dc46d224bd288d98 SHA-256: ae8b12584dbb052f61034f25e375aaa3351d82a6589cda030a3b20870605a828
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with many URLs pointing to potentially compromised WordPress upload directories or disposable hosting. The presence of external URIs suggests an attempt to redirect the user to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://coretry.ru/uplcv?utm_term=quit+tracker+app PDF link annotation
    • http://matchonusa.com/uploads/files/wibasivilakobiko.pdfIn PDF document text
    • https://anjingliar.com/contents/files/65198199820.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/31469700262.pdfIn PDF document text
    • https://www.corpeverest.com/ckfinder/userfiles/files/bukiwetodidi.pdfIn PDF document text
    • http://raylutickenterprises.com/userfiles/files/81481225261.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/42211207542.pdfIn PDF document text
    • http://wuyioutdoor.com/userfiles/file/8327695943.pdfIn PDF document text
    • https://maconlux.ovh/userfiles/files/30920030302.pdfIn PDF document text
    • http://thevisionkharj.com/userfiles/files/fifitupezewijulesedasewaz.pdfIn PDF document text
    • http://shqinze.net/admin/upimg/file///19553448738.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/13866347358.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614742754321f---titutidima.pdfIn PDF document text
    • https://sunrise-photon.com/upfiles/editor/files/2238305438.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f95d9a2fb7---vixezinizufo.pdfIn PDF document text
    • https://easypayindia.in/userfiles/file/67633005246.pdfIn PDF document text
    • https://volpatoebrum.com.br/_common/admin/scripts/ckfinder/userfiles/files/48653548459.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/zufulerakoju.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/731e6d819dc86fa72047630002973b6b/sotamevoxutilojel.pdfIn PDF document text
    • https://sreekanakananda.com/ckfinder/userfiles/files/31258763403.pdfIn PDF document text
    • https://danielfelber.ch/userfiles/file/bodudabipamuxesafavetam.pdfIn PDF document text
    • http://czyxchem.com/upload/files/68989973076.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/35811553502.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_off0000dcc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC2 17124 bytes
SHA-256: eee5f67d19d91853e7811ea6e6a9548f091c6deed27c56677e07d5f091fc62ac
font_01_sfnt_off00010906.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10906 10180 bytes
SHA-256: f0d4d7823f7eaf7f1f28009dcb24ea6620b340b1f4d9e1e44a4f006d0fdd1003
font_02_sfnt_off00012019.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12019 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1