Malicious PDF — malware analysis report

Static analysis result for SHA-256 18cdf3ee691cace8…

MALICIOUS

PDF

92.5 KB Created: 2021-08-11 13:09:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 57f93c43c80603502f72ec6135e05738 SHA-1: 768ab582f56c90d774a53671a63fd17b5550aa3d SHA-256: 18cdf3ee691cace8e1deb1d1e2fa584cb763488fe19fcf62089583821f7d4f5b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or are part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery through these links. No scripts were extracted, and the document body was unreadable, so the primary indicators are the URL structures and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9866

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 http://interstyle.org/content/xuploadimages/file/talipotikuguraba.pdf
    • http://www.mediagrand.hu//data/editorfile/givepexebixefujuxeta.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/89eacbbj3qgmfrjuv8auc6a2as/linikotejerigok.pdf
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/bujajipebusuratutix.pdf
    • https://ap-qatar.com/userfiles/files/kupatuwutejubele.pdf
    • https://pnp-studio.com/fckeditorfiles/file/7771357757.pdf
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607776930c2a1---67096301315.pdf
    • http://portableandcool.com/files/files/gokurenedaneguwa.pdf
    • http://nanobubblevietnam.com/uploads/userfiles/file/pezaxebunemez.pdf
    • http://dermaktif.com/imgup/file/35807006251.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160f1947d68a54---49080384898.pdf
    • http://ciarajewellery.com/editor_upload/file/31398227620.pdf
    • http://alarcon-v.com/editor_upload_image/file/gajikojizojepuluz.pdf
    • http://www.makattakasinti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607835a697630---lomilamujo.pdf
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/37d6ea63575db82242cf352d1ef94b7d/kalozigonogodixozemovu.pdf
    • http://szyldkj.com/luodan/images/userfiles/file/2631150391.pdf
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b2ade3919d0---zokopiwobifefekis.pdf
    • http://autoneza.cz/UserFiles/File/nugimojosedoxirute.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16105161e74194---nevopugavav.pdf
    • http://mai-colle.jp/userfiles/file/68030417866.pdf
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843d7b36439---6947375985.pdf
    • http://deborahkay.com/ckfinder/userfiles/files/22970687740.pdf
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/96c3a4436af3b099eec81340d50098ab/10363348066.pdf
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160beb39851133---4600113134.pdf
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/709f9cbc6a5fa099db3699c3cb175e94/97320233559.pdf
    • https://raiporjai.com/piceditor/file/jumivigu.pdf
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/2480ae9773250b32cf7b2f8c83584ef0/gojatelopisuru.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=how+to+use+tripp+trapp+baby+set
    • 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_off0001039f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1039F 16792 bytes
font_01_sfnt_off00011bb1.bin
7d2667610cdb1d605e45d16e46a52c3086550b4b5ee631da2d8fb18767482b99
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BB1 17968 bytes
font_02_sfnt_off00014af2.bin
779b44c2cb96865f6157a8b8c563bd4c94971dbff2d2f17937d4e6dea3512e89
pdf-font-stream PDF embedded font (sfnt) at offset 0x14AF2 10524 bytes