Malicious PDF — malware analysis report

Static analysis result for SHA-256 86e1857fc9665938…

MALICIOUS

PDF

84.3 KB Created: 2021-09-14 01:00:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6f9b72d30b72d45164fc9b64726f4b48 SHA-1: 085615b406bc529c6253ed0e26eb7e06ddd9c8df SHA-256: 86e1857fc9665938970e340d7262ec0c07e8bc6c810ddb57670cb2e0fac15c0c
126 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs, many of which point to unknown PDF files on potentially disposable domains, suggesting a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using numerous distinct, low-reputation hosts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://zahidnawaz.com/UploadedImages/image/verumusadoza.pdf In PDF document text
    • https://www.paseppe.gr/ckfinder/userfiles/files/zovanupafuvulo.pdfIn PDF document text
    • http://yomamasushitogo.com/uploads/files/gizaluxa.pdfIn PDF document text
    • http://hzeiger.com/userfiles/file/54384407067.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/68384960588.pdfIn PDF document text
    • https://servicepapik.ro/files/pilamodebatowukuri.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613e94308ac09---botinutuvifufojimetosotig.pdfIn PDF document text
    • http://www.logistiekverbeteren.nl/ckfinder/userfiles/files/sokuzekawuperiked.pdfIn PDF document text
    • https://emtracing.net/userfiles/file/31045533055.pdfIn PDF document text
    • http://airmon.hu/images/files/70957075396.pdfIn PDF document text
    • https://www.mediawerf.nl/bundles/store24backoffice/ckfinder/userfiles/files/38273860496.pdfIn PDF document text
    • http://kolesnikov.pro/ckfinder/userfiles/files/zeladefifumuk.pdfIn PDF document text
    • https://www.lsv-wittlage.de/ckfinder/userfiles/files/lopexojeketiwawam.pdfIn PDF document text
    • http://yevres.fr/ckfinder/userfiles/files/dosufavogiruf.pdfIn PDF document text
    • http://cavusofis.com/images_upload/files/81922725229.pdfIn PDF document text
    • https://www.vita-organic.eu/admin/ckfinder/userfiles/files/54643051135.pdfIn PDF document text
    • https://rent-1.es/ckfinder/userfiles/files/98745897575.pdfIn PDF document text
    • http://seattleteriyaki3.com/uploads/files/kivifegotanelumunaponij.pdfIn PDF document text
    • http://polaryachts.com/res/wysiwyg/file/50815576146.pdfIn PDF document text
    • http://www.galiantsolutions.com/emailimages/file/sitilamal.pdfIn PDF document text
    • https://openkomm.yussfone-crm.com/userfiles/file/92639468669.pdfIn PDF document text
    • https://sofupingame.net/calisma2/files/uploads/70230612167.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-9-13/20210913190226545941.pdfIn PDF document text
    • https://sahodayabbsr.com/test/fckeditor/file/69867414869.pdfIn PDF document text
    • http://haciogullari.com/depo/sayfaresim/file/89767714331.pdfIn PDF document text
    • https://jcmimoveis.com/userfiles/file/zewuzuvasevuminorupizaza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=android+mail+imapPDF 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_off0000e74b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE74B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ff62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF62 10136 bytes
SHA-256: cdf764b3d7343ba24aeb8e4a65b653270aba3e37e98626ee3f15d1b5f3e5bb63
font_02_sfnt_off000115d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D7 17876 bytes
SHA-256: 82c2b6df256c786893ffa925afe88c8bb01e67a30e1a9b07abe5cec44e0919f3