Malicious PDF — malware analysis report

Static analysis result for SHA-256 a11e1df0a78ce649…

MALICIOUS

PDF

85.3 KB Created: 2021-09-18 03:21:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e4c2cba48fbdc0aeed880c46aeafeaff SHA-1: 4932d8cf2fd06a4c62aee7f277f4dc968907967e SHA-256: a11e1df0a78ce6497a06e0e1a52f2aef96fd54018971264895944cc170246eea
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on potentially compromised CMS upload storage. The presence of numerous unknown URLs suggests a phishing or scamming attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9938

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 https://htchninc.com/d/files/golikesinikokaba.pdf
    • https://alutat.com/data/file/72991291679.pdf
    • https://peperita.it/writable/public/userfiles/file/vujim.pdf
    • http://vector-mebel.ru/uploads/files/riteloxugajivokabavo.pdf
    • https://keyword-lda.pt/site/upload/file/fureroxoxawika.pdf
    • https://tbsva.org/Upload/files/20210911210322.pdf
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/161442f994fc81---tuduwozebijemezivafu.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132979c8b8bd---11636795807.pdf
    • http://neoneophytou.com/ckfinder/userfiles/files/xikitaduferoguvugizix.pdf
    • https://tootooair.com/FileData/ckfinder/files/20210904_4066D0D2AC46427E.pdf
    • http://amongelite.com/ci/userfiles/files/wexirekazevuxosapazoli.pdf
    • https://kidneystonetreatment.in/userfiles/files/50816066729.pdf
    • http://tavaszitura.eu/userfiles/files/dasuzodi.pdf
    • http://jedwines.com/cmsCart/upload/file/lodejotibonenadoger.pdf
    • http://ourdesign.hk/ckfinder/userfiles/files/35362662830.pdf
    • http://mexxeopaint.com/upload/files/votunimeruvivubakujadus.pdf
    • http://thietbiotoviet.com/Images_upload/files/jiboxokufifodiratogepo.pdf
    • https://businesslife.com/content/files/84952545874.pdf
    • http://abwingsbuffalo.com/uploads/files/47439085758.pdf
    • https://optical-axis.com/uploads/files/202109171855466062.pdf
    • http://fkm-lux.by/var/upload/file/goxujexubadipizojewo.pdf
    • http://www.siposferenc.hu/html/65015358933.pdf
    • https://ctners.com/ckfinder/userfiles/files/vezimanuko.pdf
    • http://kfoodntea.com/dataroom/file/56437630371.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613700b473020---61484993480.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=recover+deleted+photos+pro+apk
    • 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_off0000c516.bin
5820c17c8924ca519673d5565709f8bc8b18ed33feb01f3e96017b6bfc0717df
pdf-font-stream PDF embedded font (sfnt) at offset 0xC516 23060 bytes
font_01_sfnt_off000100c5.bin
eb83fb48a2f60ac59fad768156047f025764cad4052c8f34695a9c8dd2456ad8
pdf-font-stream PDF embedded font (sfnt) at offset 0x100C5 16132 bytes
font_02_sfnt_off00011636.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11636 16792 bytes
font_03_sfnt_off00012e4d.bin
e9af1b02d6f1de036008c81ee00902daec3177c75835bc41abb8cc38225c6606
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E4D 10620 bytes