Malicious PDF — malware analysis report

Static analysis result for SHA-256 efc476f54e6ac52a…

MALICIOUS

PDF

106.8 KB Created: 2021-07-19 13:21:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f76ea409ab3eb55c3d3f49a3d38877a2 SHA-1: 5c006ec8cd27283063511f7a3177dbbeb1ac2d67 SHA-256: efc476f54e6ac52a9f6dc8520497ffc4376837fb142b4677b0c04ebe39d59809
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, pointing to numerous URLs hosted on compromised WordPress sites, likely serving as a distribution point for further malicious content. The presence of external URIs and the nature of the links suggest a phishing or malware delivery scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160943c344c23f---kifawidumoxaregebevupel.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a44ea1b8bfa---fulagazuvevirefimu.pdf
    • https://sbsoftware.ro/admin/userfiles/file/28026668396.pdf
    • http://absolutelyneon.com/userfiles/file/3732064917.pdf
    • http://hosungtour.net/FileData/ckfinder/files/20210619_3B49E9FCC523DB2B.pdf
    • https://actaviaserica.org/board/file/files/garanowokugakimokox.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608a39c700ec4---80127246781.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bc9f07e572e---183016934.pdf
    • http://infinijewelry.com/userfiles/file/90339242467.pdf
    • https://annjulieskarpmo.com/userfiles/file/34171577373.pdf
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/cef71a5f076f7248b0b5d2fa5ac49682/xulelilidopemilizodumil.pdf
    • http://interno-kazan.ru/upload/files/zogedulurere.pdf
    • https://ozmutludokum.com/userfiles/file/69872095134.pdf
    • http://mtlebanon62.com/clients/5/5e/5ee551a8be14a26d7d76bc5e90dd1372/File/20771955066.pdf
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/fd40beab51ad858196f4b24847db7694/suwukavopofem.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b50cd35e7d---70758605718.pdf
    • http://beautybybelief.com/admin/images/file/20710825981.pdf
    • http://bobmeetin.com/media/galleries/files/fefijoxudaxagesosulumuwe.pdf
    • http://thepokewave.com/uploads/files/femev.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1cf656e2e---19278175559.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16089714160565---49442984441.pdf
    • http://bmhs71.com/clients/c/c9/c97ff408e01126d63256cf68004d6641/File/lifotudukoka.pdf
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6731acd3e7---79297550148.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160953262e7a24---12103432207.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=example+lab+report+biology
    • 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_off00013ddb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13DDB 16792 bytes
font_01_sfnt_off000155ed.bin
59c6cbfaf638ae110e81e334a269e2cfa5fa606e9c6d5707901db2cd5a6f6a83
pdf-font-stream PDF embedded font (sfnt) at offset 0x155ED 18132 bytes
font_02_sfnt_off000185aa.bin
1ab7c1be47687f8fd62e588259b022c1662cd5d9a604cfc97ff6d3dd627a72a9
pdf-font-stream PDF embedded font (sfnt) at offset 0x185AA 10664 bytes