Malicious PDF — malware analysis report

Static analysis result for SHA-256 718fdf878c45fc98…

MALICIOUS

PDF

125.6 KB Created: 2021-07-05 00:19:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4d83dd3d37c83e68d65e763692d43cb2 SHA-1: b56ee36f4c0b0de163f7ef1fcd503dabb18d5703 SHA-256: 718fdf878c45fc98c384fa38c7b3cbb773d94caf15ed7b96465ed45e9df76875
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as a phishing trojan and by an ML classifier, indicating malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage, suggesting it's used to distribute further malicious content or phish users. The embedded URLs, while some are marked benign, are part of a larger pattern of directing users to potentially compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9897

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 http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607921e18eca5---33259553945.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce49975301---71056681636.pdf
    • http://southport1969.com/clients/861680/File/89680568855.pdf
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/c0ta9rg1evio8ighh9bsbldnhk/nufezovewum.pdf
    • http://goldmustang.com/files/files/xepejufepoxuw.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073817ae3289---walufupeteg.pdf
    • https://olterus.org/contents//files/gupasabawi.pdf
    • https://strechybenesov.cz/content/vexusezutagugodepiga.pdf
    • http://studioriggio.it/userfiles/files/88391404566.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607669488b191---14165361799.pdf
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/51e65049691d4cd33c4bd2ba38d4db21/88618528717.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/5fc341bda5f6f81b1e52ea82e097b3e6/fiwemawobawemibetisidut.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/48krgrn0de1qbilrcsj8l5edg7/puxomipe.pdf
    • https://kvkumariajnkvv.org/singhania/downloads/file/54807911840.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16093d39f2b2c6---seseju.pdf
    • https://weddingitaly.jp/images/file/rorageganuzofewosikajujif.pdf
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/410d032c9f3d13d3557c9167e9a555ed/kebagejemozutuvewo.pdf
    • http://analogsys.com/uploaded/file/58752225360caa3dd38288.pdf
    • https://contact-house.com/fckeditor/upload/file/vilixakemawepitu.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082ef10ea971---40934055994.pdf
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/ae356b9184297434206a684af64f27ea/pebisitapalaxulimilifaz.pdf
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/1607dda51b451f---97898426353.pdf
    • https://akproauto.com/nbloom/fckuploads/file/lagonidezetazodaxapigipi.pdf
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089af776f3dd---fegebo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=self+induction+definition
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00016a03.bin
f1423489faa2c176592b3343b364d6dcc26fd685885d163b1b139c1e8ca10e39
pdf-font-stream PDF embedded font (sfnt) at offset 0x16A03 21284 bytes
font_01_sfnt_off0001a2e9.bin
d49cd2e1dfe18d5feeb756d8c64acc27085e230f40cbffde8991e7cba9eb10cf
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A2E9 16384 bytes
font_02_sfnt_off0001b97e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B97E 16792 bytes
font_03_sfnt_off0001d195.bin
36c4fe54de545c765afbbd0a92bd6e805211cace1d3b75c8052b06d60aaeb403
pdf-font-stream PDF embedded font (sfnt) at offset 0x1D195 10212 bytes