Malicious PDF — malware analysis report

Static analysis result for SHA-256 f08391a48dcfb5a8…

MALICIOUS

PDF

99.7 KB Created: 2021-07-05 15:34:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 16350039ad8eaeb20107861bee030c16 SHA-1: df86f9b7a8b9acc70719e89f5d840bc2c1601289 SHA-256: f08391a48dcfb5a829cb6f68a7a9468fb8183bc138b410f967f1bea02c7bc9c2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple distinct hosts, many of which are associated with compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bbb476b2739---5125987401.pdf In PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/1f56f1cf334f674eac2eccd35209606f/wenosop.pdfIn PDF document text
    • http://lesbambousbleus.fr/ckeditor/upload/files/pegedubupudokeko.pdfIn PDF document text
    • https://nisahanpin.com/calisma2/files/uploads/37426029935.pdfIn PDF document text
    • http://bahtiyardishekimi.com/fckfiles/file/fuwesifexafoxolepip.pdfIn PDF document text
    • http://cjatkinson.com/userimages/belafibifekogemerekeberu.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081e98fb673c---xosirepefepuvatexapamosi.pdfIn PDF document text
    • http://goldenpoolandsauna.com/user_img/files/jodanedoziju.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/0b0731f26fe3f59f60f73f3f7f6992d7/45116578693.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/ibufoxodenidujasa.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/91807794315.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5f6878e6a---sobolukaxerupax.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/68c643babd1927201f70c566aa42adc3/fisolexizumavuzigigovij.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/e06d8df786433df57f5397bd51c8e5f3/kufimow.pdfIn PDF document text
    • https://adepotcustom.com/UploadFiles/file/20210613195926139.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/lijeju.pdfIn PDF document text
    • https://scavilecis.it/userfiles/file/bakuwaxewapurutozapedu.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/46161147202.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160add7e87929f---nifonureruguti.pdfIn PDF document text
    • http://cuspsurgeons.com/userfiles/file/45764019621.pdfIn PDF document text
    • http://waltwhitman1964grads.com/clients/6/6c/6c9ae932573016e5ff31759a10dce4b4/File/bakejexuwiluzepa.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/xawafek.pdfIn PDF document text
    • http://dharmapremipariwar.org/userfiles/file/86698439048.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/88f80a4dfeb28dd38a92e997111ac91c/wesuvivowofidu.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ff66ce38a6---rojuxinonaterivozun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=environmental+pollution+mcq+with+answersPDF link annotation
    • 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_off00012389.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12389 11020 bytes
SHA-256: 9e935a79ff29fffafa9ccfa6fd23fa5054dc7c0a612d656da8c20e5407d92c64
font_01_sfnt_off00013d05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D05 16948 bytes
SHA-256: 9cd437dd0b8c7d67f304d3d6f41e2be3c538245ccf6541c7592f3be0aaa075ec
font_02_sfnt_off0001695b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1695B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1