Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf4b910760068e0c…

MALICIOUS

PDF

87.4 KB Created: 2021-07-08 10:16:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d69bb8e25839e8fa0b737bc1201fbad5 SHA-1: a57c9fdeae70eec29bda8acbe71150ff448b12f4 SHA-256: cf4b910760068e0c2e3ca84b9860fa129721881b1fcfe44bf39c26fb7c526783
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external sites, many of which host other PDFs, suggesting a link farm designed to distribute malicious content. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs the user to open a password-protected archive, a common tactic to bypass security filters. The ClamAV detection further confirms its malicious nature, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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
  • 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=recover+data+from+locked+android+phone+with+broken+screen
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/302d876a62f6c560505d9b321d7fbb1c/79205385620.pdf
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/gcpitaen9b0dcfris2vp9kljf2/rusanasijolegosurap.pdf
    • http://trendybiz.in/usersfiles/file/14260570483.pdf
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090b92566627---wanosutudesegepon.pdf
    • http://bassbasement.org/userfiles/file/poxurat.pdf
    • http://el-master.ru/userfiles/file/jakeriwididutorakusufirij.pdf
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d53e8ec40e4cdc393d256dc0a048abac/97463221028.pdf
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160e0ba4a94713---58354438174.pdf
    • http://haniltm.kr/upfiles/editor/files/gajukatasavewadujuj.pdf
    • https://robert-zauer.cz/userfiles/file/vexilo.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160dcea3ae954f---majazakud.pdf
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/16079f09d26191---wusilovama.pdf
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/hv3b7i7ev35qrmhv1spn3e7bdp/salogujepetukedezasa.pdf
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6546700e39---fomesazep.pdf
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609e8a5e6874e---62583805912.pdf
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/bbb835c7e4aff9a0a857aff7e4d65720/weruvuna.pdf
    • https://elearning-chemistry.ro/userfiles/file/wenupubijanofanefesari.pdf
    • https://cambodiadriverservice.com/userfiles/file/ruwosadoxofezoteka.pdf
    • http://lungtransplantopen.com/clients/d/de/de7cc03d42bda6b8b84c8ac9728529bb/File/lufed.pdf
    • http://apartamentosalbatros.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4ae5bbef7c---dozagibobidapulawen.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0a10bab95---89517153463.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f2a6.bin
fb25aa149ae88f96248acab836a22a5b29af17005227918727c5f4219e3dc094
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A6 11316 bytes
font_01_sfnt_off00010cdd.bin
76caac95c08991d91463bd6fbc1325276f865ffb1aba4aa70e9bd5726832a143
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CDD 16616 bytes
font_02_sfnt_off000137e9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x137E9 16792 bytes