Malicious PDF — malware analysis report

Static analysis result for SHA-256 3508306f1ff633de…

MALICIOUS

PDF

81.4 KB Created: 2021-09-16 04:05:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 05d06c1234691da7a73e66b6a80420ba SHA-1: 9fe9761729a801ced7bf360a0f7579d7a6f44749 SHA-256: 3508306f1ff633deebdff6d3f28936fb0299afb56ff99b86d426cffd76404041
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of multiple external URLs, including one disguised as a guide to bypass Android screen locks, suggests a phishing or social engineering lure. The 'SE_PASSWORD_ARCHIVE_LURE' heuristic further supports this, indicating the document may be a precursor to delivering a password-protected malicious archive.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://crewmak.ru/uplcv?utm_term=how+to+bypass+screen+pattern+lock+on+android PDF link annotation
    • http://indagosrl.it/userfiles/files/sufefibi.pdfIn PDF document text
    • https://goldmenu.com/userfiles/file/nuxoguboveni.pdfIn PDF document text
    • http://delve-cr.com/uploads/36554915875.pdfIn PDF document text
    • https://www.gullyracing.it/admin/ckfinder/userfiles/files/42890841853.pdfIn PDF document text
    • http://quangcongluc.com/upload/files/fixazojitiremanobami.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///jadowutipawo.pdfIn PDF document text
    • https://pragatitic.org/ckfinder/userfiles/files/55804012899.pdfIn PDF document text
    • https://movimientofamiliadejesus.com/images/uploaded/file/kedujo.pdfIn PDF document text
    • http://datcat.vn/2018/file/57595758637.pdfIn PDF document text
    • http://chafewyuok.handysociality.com/upload/files/totexatibisakuxel.pdfIn PDF document text
    • https://eclearusa.com/images/file/didoga.pdfIn PDF document text
    • https://fereshtegan.net/basefile/fereshtegannet/files/85699798698.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e4bc6d2ce4---ziguvopuxirefo.pdfIn PDF document text
    • http://www.wiz-fac.com/uploadImg/file/34396473231.pdfIn PDF document text
    • http://ammk.sk/userfiles/file/nexiboxuzolusawi.pdfIn PDF document text
    • https://crc.creativechange.net/ckfinder/userfiles/files/65925168461.pdfIn PDF document text
    • https://kapefashion.com/files/files/xoboxuditagarusovijawepa.pdfIn PDF document text
    • https://rakowka.pl/userfiles/file/fezokenoluwedamirubusadov.pdfIn PDF document text
    • https://mongolia-volkslift.com/uploads/files/tobebebomelasopinedi.pdfIn PDF document text
    • http://baltyk.recykling-rejs.pl/imgturysta/files/zifena.pdfIn PDF document text
    • http://abwingsde.com/uploads/files/likovutegexitelo.pdfIn PDF document text
    • http://tobn56.com/UpFiles/file/39187635199.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_off0000d8f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F8 17664 bytes
SHA-256: 729ff68f8e1e55f61cc51c38dd509d30379a3364b40c72e2a5b17aa388240969
font_01_sfnt_off00010639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10639 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E50 10928 bytes
SHA-256: 9ba621cd419bed26e559b820bbfaebe00688e6dcd0798e9cb2d395a808d8ff0e