Malicious PDF — malware analysis report

Static analysis result for SHA-256 23f87e61156828a8…

MALICIOUS

PDF

86.3 KB Created: 2021-08-04 18:36:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2ab34cd56a87ae4a02af9aa459c35359 SHA-1: 9193d8cb09d045431459a09c36203d87b05eb8ca SHA-256: 23f87e61156828a87157ffc3fb4c1b035d10a4832cc1093b144449c601cd0154
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. The document contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content or conduct phishing. No scripts were extracted, but the presence of numerous external links indicates a redirection mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/9cfc147d2a399be9644b5dcfd8037bda/weluwabofebobosezu.pdf
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/44d2cdf49da55413d8ae9941f88403dd/20269771339.pdf
    • http://ubestsports.com/imager/files/20210620173228.pdf
    • https://vzglavniki.net/data/file/lixedizusufox.pdf
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/16071c851216fa---nijunajuzeseravexopimede.pdf
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c3555cdde02---kaxufawuluboved.pdf
    • http://pereplanirovkaoblast.ru/pict/file/wepusi.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbd4270e576---jesepuxuk.pdf
    • https://jxloanchien.com/style/postimage/file/86271891975.pdf
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc53562ff8---pafumawiwafolubisu.pdf
    • http://dnepropress.net/files/file/napude.pdf
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/8acd6249f0e29fb54ec5b699d490f991/sixaxaxum.pdf
    • http://zonazero.es/userfiles/file/xaderutedu.pdf
    • http://yngc.ru/admin/ckfinder/userfiles/files/1487376061.pdf
    • https://flexrocksrollovers.com/wp-content/plugins/super-forms/uploads/php/files/psbrcpkpqsm4sfinpsm080chvs/kurilejokokerux.pdf
    • http://codienlanhminhquang.com/upload/files/45351491096.pdf
    • https://okud-istra.hr/userfiles/file/94686332382.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7ac0deb2f3d9cc792ac956fffdccfefe/83456498489.pdf
    • http://inbond-cn.com/userfiles/file/toxevemafuvomezutagolab.pdf
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160e13fbad37b8---95221370609.pdf
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c322d0078c4---15227382331.pdf
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096b885eae32---kelawutijajudo.pdf
    • http://hobbstownis100.com/clients/6/66/66141d04a4341350d76ae3a38785cb5a/File/80215576526.pdf
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160fde4b165954---jiguwidubijiguvafiwapi.pdf
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/160cc33aaebb65---janukakutaseloniratelus.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=exercices+sur+adjectifs+epithete+et+attribut
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cb95.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB95 16792 bytes
font_01_sfnt_off0000e3a7.bin
9f39ebbeaf039820241c967e32d8794f42965c71e7a33cf58f65e9d97f8dc7f9
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A7 18220 bytes
font_02_sfnt_off000111e6.bin
b711b92a95f65213dd0f1e958304897867cb15e41607e416f5318dd51e4b8913
pdf-font-stream PDF embedded font (sfnt) at offset 0x111E6 10904 bytes
font_03_sfnt_off00012afc.bin
e3a1ca7fbcde87b6e2bc585668cff1a50452d2a09c95c546c16e9f90aebd6500
pdf-font-stream PDF embedded font (sfnt) at offset 0x12AFC 1636 bytes
font_04_sfnt_off000132c8.bin
9d5144547e0b729630886a3ad3ce48e7da84b0115899dd9c2390406af6f0fecd
pdf-font-stream PDF embedded font (sfnt) at offset 0x132C8 16092 bytes